61395840 has 512 divisors, whose sum is σ = 264384000. Its totient is φ = 13271040.

The previous prime is 61395833. The next prime is 61395853. The reversal of 61395840 is 4859316.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 61395795 and 61395804.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 3231351 + ... + 3231369.

It is an arithmetic number, because the mean of its divisors is an integer number (516375).

Almost surely, 2^61395840 is an apocalyptic number.

61395840 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 61395840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132192000).

61395840 is an abundant number, since it is smaller than the sum of its proper divisors (202988160).

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

61395840 is a wasteful number, since it uses less digits than its factorization.

61395840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 61395840 is about 7835.5497573559. The cubic root of 61395840 is about 394.4993711046.

The spelling of 61395840 in words is "sixty-one million, three hundred ninety-five thousand, eight hundred forty".