688566157 has 4 divisors (see below), whose sum is σ = 718503840. Its totient is φ = 658628476.

The previous prime is 688566119. The next prime is 688566199. The reversal of 688566157 is 751665886.

688566157 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 688566157 - 2²⁷ = 554348429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688566457) 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, 14968807 + ... + 14968852.

It is an arithmetic number, because the mean of its divisors is an integer number (179625960).

Almost surely, 2^688566157 is an apocalyptic number.

It is an amenable number.

688566157 is a deficient number, since it is larger than the sum of its proper divisors (29937683).

688566157 is a wasteful number, since it uses less digits than its factorization.

688566157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29937682.

The product of its digits is 2419200, while the sum is 52.

The square root of 688566157 is about 26240.5441445104. The cubic root of 688566157 is about 883.0430791781.

The spelling of 688566157 in words is "six hundred eighty-eight million, five hundred sixty-six thousand, one hundred fifty-seven".