68405904 has 80 divisors (see below), whose sum is σ = 224410240. Its totient is φ = 19543680.

The previous prime is 68405903. The next prime is 68405921. The reversal of 68405904 is 40950486.

68405904 is a `hidden beast` number, since 68 + 4 + 0 + 590 + 4 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (68405903) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8287 + ... + 14334.

It is an arithmetic number, because the mean of its divisors is an integer number (2805128).

Almost surely, 2^68405904 is an apocalyptic number.

It is an amenable number.

68405904 is an abundant number, since it is smaller than the sum of its proper divisors (156004336).

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

68405904 is a wasteful number, since it uses less digits than its factorization.

68405904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22645 (or 22633 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 68405904 is about 8270.7861778673. The cubic root of 68405904 is about 408.9760369188.

The spelling of 68405904 in words is "sixty-eight million, four hundred five thousand, nine hundred four".