665677690 has 16 divisors (see below), whose sum is σ = 1201245192. Its totient is φ = 265598784.

The previous prime is 665677643. The next prime is 665677697. The reversal of 665677690 is 96776566.

It can be written as a sum of positive squares in 4 ways, for example, as 484748289 + 180929401 = 22017^2 + 13451^2 .

It is a super-2 number, since 2×665677690² = 886253573927472200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (665677697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79869 + ... + 87808.

Almost surely, 2^665677690 is an apocalyptic number.

665677690 is a deficient number, since it is larger than the sum of its proper divisors (535567502).

665677690 is a wasteful number, since it uses less digits than its factorization.

665677690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168081.

The product of its (nonzero) digits is 2857680, while the sum is 52.

The square root of 665677690 is about 25800.7304160173. The cubic root of 665677690 is about 873.1482756053.

The spelling of 665677690 in words is "six hundred sixty-five million, six hundred seventy-seven thousand, six hundred ninety".