68639831 has 8 divisors (see below), whose sum is σ = 73985520. Its totient is φ = 63303552.

The previous prime is 68639827. The next prime is 68639849. The reversal of 68639831 is 13893686.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 68639831 - 2² = 68639827 is a prime.

It is a super-2 number, since 2×68639831² = 9422852799417122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68639821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22940 + ... + 25758.

It is an arithmetic number, because the mean of its divisors is an integer number (9248190).

Almost surely, 2^68639831 is an apocalyptic number.

68639831 is a deficient number, since it is larger than the sum of its proper divisors (5345689).

68639831 is a wasteful number, since it uses less digits than its factorization.

68639831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4705.

The product of its digits is 186624, while the sum is 44.

The square root of 68639831 is about 8284.9158716308. The cubic root of 68639831 is about 409.4416969665.

The spelling of 68639831 in words is "sixty-eight million, six hundred thirty-nine thousand, eight hundred thirty-one".