688795531 has 4 divisors (see below), whose sum is σ = 705595464. Its totient is φ = 671995600.

The previous prime is 688795517. The next prime is 688795573. The reversal of 688795531 is 135597886.

688795531 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 an emirpimes, since its reverse is a distinct semiprime: 135597886 = 2 ⋅67798943.

It is a cyclic number.

It is not a de Polignac number, because 688795531 - 2²¹ = 686698379 is a prime.

It is a super-2 number, since 2×688795531² = 948878567051143922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688795631) 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, 8399905 + ... + 8399986.

It is an arithmetic number, because the mean of its divisors is an integer number (176398866).

Almost surely, 2^688795531 is an apocalyptic number.

688795531 is a deficient number, since it is larger than the sum of its proper divisors (16799933).

688795531 is a wasteful number, since it uses less digits than its factorization.

688795531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16799932.

The product of its digits is 1814400, while the sum is 52.

The square root of 688795531 is about 26244.9143835525. The cubic root of 688795531 is about 883.1411209008.

The spelling of 688795531 in words is "six hundred eighty-eight million, seven hundred ninety-five thousand, five hundred thirty-one".