688357431 has 6 divisors (see below), whose sum is σ = 994294080. Its totient is φ = 458904948.

The previous prime is 688357391. The next prime is 688357451. The reversal of 688357431 is 134753886.

It is not a de Polignac number, because 688357431 - 2⁷ = 688357303 is a prime.

It is a super-2 number, since 2×688357431² = 947671905625839522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688357451) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38242071 + ... + 38242088.

It is an arithmetic number, because the mean of its divisors is an integer number (165715680).

Almost surely, 2^688357431 is an apocalyptic number.

688357431 is a deficient number, since it is larger than the sum of its proper divisors (305936649).

688357431 is a wasteful number, since it uses less digits than its factorization.

688357431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76484165 (or 76484162 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

The square root of 688357431 is about 26236.5666770635. The cubic root of 688357431 is about 882.9538441425.

The spelling of 688357431 in words is "six hundred eighty-eight million, three hundred fifty-seven thousand, four hundred thirty-one".