68639864 has 16 divisors (see below), whose sum is σ = 128787720. Its totient is φ = 34296480.

The previous prime is 68639849. The next prime is 68639869. The reversal of 68639864 is 46893686.

It is a super-2 number, since 2×68639864² = 9422861859876992, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68639869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20894 + ... + 23954.

Almost surely, 2^68639864 is an apocalyptic number.

It is an amenable number.

68639864 is a deficient number, since it is larger than the sum of its proper divisors (60147856).

68639864 is a wasteful number, since it uses less digits than its factorization.

68639864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5870 (or 5866 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 50.

The square root of 68639864 is about 8284.9178632018. The cubic root of 68639864 is about 409.4417625823.

The spelling of 68639864 in words is "sixty-eight million, six hundred thirty-nine thousand, eight hundred sixty-four".