671690889 has 27 divisors (see below), whose sum is σ = 994975527. Its totient is φ = 436649616.

The previous prime is 671690849. The next prime is 671690909. The reversal of 671690889 is 988096176.

The square root of 671690889 is 25917.

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

It can be written as a sum of positive squares in only one way, i.e., 484220025 + 187470864 = 22005^2 + 13692^2 .

It is not a de Polignac number, because 671690889 - 2²¹ = 669593737 is a prime.

It is a super-2 number, since 2×671690889² = 902337300731220642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (671690849) 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, 4120722 + ... + 4120884.

Almost surely, 2^671690889 is an apocalyptic number.

671690889 is the 25917-th square number.

671690889 is the 12959-th centered octagonal number.

It is an amenable number.

671690889 is a deficient number, since it is larger than the sum of its proper divisors (323284638).

671690889 is an equidigital number, since it uses as much as digits as its factorization.

671690889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438 (or 219 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 54.

The cubic root of 671690889 is about 875.7695060367.

The spelling of 671690889 in words is "six hundred seventy-one million, six hundred ninety thousand, eight hundred eighty-nine".