666009358638 has 64 divisors (see below), whose sum is σ = 1441735680000. Its totient is φ = 203890296960.

The previous prime is 666009358621. The next prime is 666009358639. The reversal of 666009358638 is 836853900666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666009358639) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 94613523 + ... + 94620561.

It is an arithmetic number, because the mean of its divisors is an integer number (22527120000).

Almost surely, 2^666009358638 is an apocalyptic number.

666009358638 is an abundant number, since it is smaller than the sum of its proper divisors (775726321362).

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

666009358638 is a wasteful number, since it uses less digits than its factorization.

666009358638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13017.

The product of its (nonzero) digits is 33592320, while the sum is 60.

The spelling of 666009358638 in words is "six hundred sixty-six billion, nine million, three hundred fifty-eight thousand, six hundred thirty-eight".