61515424404 has 240 divisors, whose sum is σ = 193795768320. Its totient is φ = 16621899840.

The previous prime is 61515424403. The next prime is 61515424447. The reversal of 61515424404 is 40442451516.

61515424404 is a `hidden beast` number, since 61 + 5 + 154 + 2 + 440 + 4 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61515424403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 39256029 + ... + 39257595.

It is an arithmetic number, because the mean of its divisors is an integer number (807482368).

Almost surely, 2^61515424404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61515424404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96897884160).

61515424404 is an abundant number, since it is smaller than the sum of its proper divisors (132280343916).

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

61515424404 is a wasteful number, since it uses less digits than its factorization.

61515424404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2520 (or 2509 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 36.

The spelling of 61515424404 in words is "sixty-one billion, five hundred fifteen million, four hundred twenty-four thousand, four hundred four".