664539908 has 6 divisors (see below), whose sum is σ = 1162944846. Its totient is φ = 332269952.

The previous prime is 664539893. The next prime is 664539923. The reversal of 664539908 is 809935466.

It is an interprime number because it is at equal distance from previous prime (664539893) and next prime (664539923).

It can be written as a sum of positive squares in only one way, i.e., 548590084 + 115949824 = 23422^2 + 10768^2 .

It is a super-2 number, since 2×664539908² = 883226578649296928, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83067485 + ... + 83067492.

It is an arithmetic number, because the mean of its divisors is an integer number (193824141).

Almost surely, 2^664539908 is an apocalyptic number.

It is an amenable number.

664539908 is a deficient number, since it is larger than the sum of its proper divisors (498404938).

664539908 is a wasteful number, since it uses less digits than its factorization.

664539908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166134981 (or 166134979 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 50.

The square root of 664539908 is about 25778.6715716695. The cubic root of 664539908 is about 872.6505277462.

The spelling of 664539908 in words is "six hundred sixty-four million, five hundred thirty-nine thousand, nine hundred eight".