688361531 has 8 divisors (see below), whose sum is σ = 808704624. Its totient is φ = 577645920.

The previous prime is 688361519. The next prime is 688361573. The reversal of 688361531 is 135163886.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-688361531 is a prime.

It is a super-2 number, since 2×688361531² = 947683194721327922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (688361581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2406716 + ... + 2407001.

It is an arithmetic number, because the mean of its divisors is an integer number (101088078).

Almost surely, 2^688361531 is an apocalyptic number.

688361531 is a deficient number, since it is larger than the sum of its proper divisors (120343093).

688361531 is a wasteful number, since it uses less digits than its factorization.

688361531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4813741.

The product of its digits is 103680, while the sum is 41.

The square root of 688361531 is about 26236.6448121706. The cubic root of 688361531 is about 882.9555971579.

The spelling of 688361531 in words is "six hundred eighty-eight million, three hundred sixty-one thousand, five hundred thirty-one".