688460257 has 4 divisors (see below), whose sum is σ = 688600836. Its totient is φ = 688319680.

The previous prime is 688460251. The next prime is 688460327. The reversal of 688460257 is 752064886.

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

It can be written as a sum of positive squares in 2 ways, for example, as 226683136 + 461777121 = 15056^2 + 21489^2 .

It is a cyclic number.

It is not a de Polignac number, because 688460257 - 2³ = 688460249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688460251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62668 + ... + 72829.

It is an arithmetic number, because the mean of its divisors is an integer number (172150209).

Almost surely, 2^688460257 is an apocalyptic number.

It is an amenable number.

688460257 is a deficient number, since it is larger than the sum of its proper divisors (140579).

688460257 is a wasteful number, since it uses less digits than its factorization.

688460257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140578.

The product of its (nonzero) digits is 645120, while the sum is 46.

The square root of 688460257 is about 26238.5261971781. The cubic root of 688460257 is about 882.9978068124.

The spelling of 688460257 in words is "six hundred eighty-eight million, four hundred sixty thousand, two hundred fifty-seven".