61684907904 has 96 divisors (see below), whose sum is σ = 178000383600. Its totient is φ = 20504223744.

The previous prime is 61684907897. The next prime is 61684907959. The reversal of 61684907904 is 40970948616.

61684907904 is a `hidden beast` number, since 6 + 1 + 68 + 490 + 7 + 90 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 338992 + ... + 488144.

Almost surely, 2^61684907904 is an apocalyptic number.

61684907904 is a gapful number since it is divisible by the number (64) 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 61684907904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89000191800).

61684907904 is an abundant number, since it is smaller than the sum of its proper divisors (116315475696).

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

61684907904 is a wasteful number, since it uses less digits than its factorization.

61684907904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149532 (or 149517 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The spelling of 61684907904 in words is "sixty-one billion, six hundred eighty-four million, nine hundred seven thousand, nine hundred four".