666905505796 has 6 divisors (see below), whose sum is σ = 1167084635150. Its totient is φ = 333452752896.

The previous prime is 666905505787. The next prime is 666905505841. The reversal of 666905505796 is 697505509666.

It can be written as a sum of positive squares in only one way, i.e., 392815562500 + 274089943296 = 626750^2 + 523536^2 .

It is a super-2 number, since 2×666905505796² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83363188221 + ... + 83363188228.

Almost surely, 2^666905505796 is an apocalyptic number.

It is an amenable number.

666905505796 is a deficient number, since it is larger than the sum of its proper divisors (500179129354).

666905505796 is a wasteful number, since it uses less digits than its factorization.

666905505796 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166726376453 (or 166726376451 counting only the distinct ones).

The product of its (nonzero) digits is 91854000, while the sum is 64.

The spelling of 666905505796 in words is "six hundred sixty-six billion, nine hundred five million, five hundred five thousand, seven hundred ninety-six".