688695049 has 27 divisors (see below), whose sum is σ = 842650893. Its totient is φ = 561180312.

The previous prime is 688695037. The next prime is 688695113. The reversal of 688695049 is 940596886.

The square root of 688695049 is 26243.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 688695049 - 2⁵ = 688695017 is a prime.

It is a super-2 number, since 2×688695049² = 948601741034224802, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (688695149) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4225042 + ... + 4225204.

Almost surely, 2^688695049 is an apocalyptic number.

688695049 is the 26243-rd square number.

688695049 is the 13122-nd centered octagonal number.

It is an amenable number.

688695049 is a deficient number, since it is larger than the sum of its proper divisors (153955844).

688695049 is an equidigital number, since it uses as much as digits as its factorization.

688695049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386 (or 193 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 55.

The cubic root of 688695049 is about 883.0981743864.

The spelling of 688695049 in words is "six hundred eighty-eight million, six hundred ninety-five thousand, forty-nine".