664745810 has 8 divisors (see below), whose sum is σ = 1196542476. Its totient is φ = 265898320.

The previous prime is 664745797. The next prime is 664745843. The reversal of 664745810 is 18547466.

It can be written as a sum of positive squares in 2 ways, for example, as 664659961 + 85849 = 25781^2 + 293^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×664745810² = 883773983825112200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33237281 + ... + 33237300.

Almost surely, 2^664745810 is an apocalyptic number.

664745810 is a deficient number, since it is larger than the sum of its proper divisors (531796666).

664745810 is a wasteful number, since it uses less digits than its factorization.

664745810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66474588.

The product of its (nonzero) digits is 161280, while the sum is 41.

The square root of 664745810 is about 25782.6649126889. The cubic root of 664745810 is about 872.7406462038.

The spelling of 664745810 in words is "six hundred sixty-four million, seven hundred forty-five thousand, eight hundred ten".