666813536 has 24 divisors (see below), whose sum is σ = 1330777224. Its totient is φ = 328838400.

The previous prime is 666813527. The next prime is 666813557. The reversal of 666813536 is 635318666.

666813536 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

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, 140390 + ... + 145061.

It is an arithmetic number, because the mean of its divisors is an integer number (55449051).

Almost surely, 2^666813536 is an apocalyptic number.

It is an amenable number.

666813536 is a deficient number, since it is larger than the sum of its proper divisors (663963688).

666813536 is a wasteful number, since it uses less digits than its factorization.

666813536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285534 (or 285526 counting only the distinct ones).

The product of its digits is 466560, while the sum is 44.

The square root of 666813536 is about 25822.7329305014. The cubic root of 666813536 is about 873.6446111162.

The spelling of 666813536 in words is "six hundred sixty-six million, eight hundred thirteen thousand, five hundred thirty-six".