665642612 has 6 divisors (see below), whose sum is σ = 1164874578. Its totient is φ = 332821304.

The previous prime is 665642573. The next prime is 665642647. The reversal of 665642612 is 216246566.

It can be written as a sum of positive squares in only one way, i.e., 437813776 + 227828836 = 20924^2 + 15094^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83205323 + ... + 83205330.

It is an arithmetic number, because the mean of its divisors is an integer number (194145763).

Almost surely, 2^665642612 is an apocalyptic number.

It is an amenable number.

665642612 is a deficient number, since it is larger than the sum of its proper divisors (499231966).

665642612 is a wasteful number, since it uses less digits than its factorization.

665642612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166410657 (or 166410655 counting only the distinct ones).

The product of its digits is 103680, while the sum is 38.

The square root of 665642612 is about 25800.0506201054. The cubic root of 665642612 is about 873.1329384365.

The spelling of 665642612 in words is "six hundred sixty-five million, six hundred forty-two thousand, six hundred twelve".