61378824240 has 120 divisors (see below), whose sum is σ = 206789874720. Its totient is φ = 16315333632.

The previous prime is 61378824239. The next prime is 61378824253. The reversal of 61378824240 is 4242887316.

It is a happy number.

61378824240 is a `hidden beast` number, since 613 + 7 + 8 + 8 + 2 + 4 + 24 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89181 + ... + 361539.

It is an arithmetic number, because the mean of its divisors is an integer number (1723248956).

Almost surely, 2^61378824240 is an apocalyptic number.

61378824240 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 61378824240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103394937360).

61378824240 is an abundant number, since it is smaller than the sum of its proper divisors (145411050480).

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

61378824240 is a wasteful number, since it uses less digits than its factorization.

61378824240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272691 (or 272682 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 45.

The spelling of 61378824240 in words is "sixty-one billion, three hundred seventy-eight million, eight hundred twenty-four thousand, two hundred forty".