61501440000 has 1280 divisors, whose sum is σ = 275158920960. Its totient is φ = 11796480000.

The previous prime is 61501439999. The next prime is 61501440001. The reversal of 61501440000 is 4410516.

It is an interprime number because it is at equal distance from previous prime (61501439999) and next prime (61501440001).

It is a tau number, because it is divible by the number of its divisors (1280).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Saint-Exupery number, since it is equal to the product of the sides of a Pythagorean triangle: 5200 × 2640 × 4480.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61501440001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4730879994 + ... + 4730880006.

It is an arithmetic number, because the mean of its divisors is an integer number (214967907).

Almost surely, 2^61501440000 is an apocalyptic number.

61501440000 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61501440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137579460480).

61501440000 is an abundant number, since it is smaller than the sum of its proper divisors (213657480960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61501440000 is an equidigital number, since it uses as much as digits as its factorization.

61501440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 61501440000 its reverse (4410516), we get a palindrome (61505850516).

It can be divided in two parts, 61501 and 440000, that added together give a triangular number (501501 = T₁₀₀₁).

The spelling of 61501440000 in words is "sixty-one billion, five hundred one million, four hundred forty thousand".