668772636 has 48 divisors (see below), whose sum is σ = 1824877824. Its totient is φ = 186633216.

The previous prime is 668772623. The next prime is 668772647. The reversal of 668772636 is 636277866.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88965 + ... + 96188.

It is an arithmetic number, because the mean of its divisors is an integer number (38018288).

Almost surely, 2^668772636 is an apocalyptic number.

It is an amenable number.

668772636 is an abundant number, since it is smaller than the sum of its proper divisors (1156105188).

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

668772636 is a wasteful number, since it uses less digits than its factorization.

668772636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185210 (or 185208 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 51.

The square root of 668772636 is about 25860.6387392114. The cubic root of 668772636 is about 874.4993646614.

The spelling of 668772636 in words is "six hundred sixty-eight million, seven hundred seventy-two thousand, six hundred thirty-six".