68557831 has 4 divisors (see below), whose sum is σ = 68755752. Its totient is φ = 68359912.

The previous prime is 68557829. The next prime is 68557843. The reversal of 68557831 is 13875586.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 68557831 - 2¹ = 68557829 is a prime.

It is a super-2 number, since 2×68557831² = 9400352382849122, 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 (68557861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98440 + ... + 99133.

It is an arithmetic number, because the mean of its divisors is an integer number (17188938).

Almost surely, 2^68557831 is an apocalyptic number.

68557831 is a deficient number, since it is larger than the sum of its proper divisors (197921).

68557831 is a wasteful number, since it uses less digits than its factorization.

68557831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197920.

The product of its digits is 201600, while the sum is 43.

The square root of 68557831 is about 8279.9656400253. The cubic root of 68557831 is about 409.2785866302.

The spelling of 68557831 in words is "sixty-eight million, five hundred fifty-seven thousand, eight hundred thirty-one".