665131538108 has 24 divisors (see below), whose sum is σ = 1202039537664. Its totient is φ = 321700806000.

The previous prime is 665131538101. The next prime is 665131538111. The reversal of 665131538108 is 801835131566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665131538101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 849260 + ... + 1432307.

It is an arithmetic number, because the mean of its divisors is an integer number (50084980736).

Almost surely, 2^665131538108 is an apocalyptic number.

It is an amenable number.

665131538108 is a deficient number, since it is larger than the sum of its proper divisors (536907999556).

665131538108 is a wasteful number, since it uses less digits than its factorization.

665131538108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2283953 (or 2283951 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 47.

The spelling of 665131538108 in words is "six hundred sixty-five billion, one hundred thirty-one million, five hundred thirty-eight thousand, one hundred eight".