664431236 has 12 divisors (see below), whose sum is σ = 1328862528. Its totient is φ = 284756232.

The previous prime is 664431223. The next prime is 664431289. The reversal of 664431236 is 632134466.

664431236 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 664431196 and 664431205.

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, 11864816 + ... + 11864871.

It is an arithmetic number, because the mean of its divisors is an integer number (110738544).

Almost surely, 2^664431236 is an apocalyptic number.

It is an amenable number.

664431236 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

664431236 is a wasteful number, since it uses less digits than its factorization.

664431236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23729698 (or 23729696 counting only the distinct ones).

The product of its digits is 62208, while the sum is 35.

The square root of 664431236 is about 25776.5636965054. The cubic root of 664431236 is about 872.6029570652.

The spelling of 664431236 in words is "six hundred sixty-four million, four hundred thirty-one thousand, two hundred thirty-six".