166316661331 has 2 divisors, whose sum is σ = 166316661332. Its totient is φ = 166316661330.

The previous prime is 166316661311. The next prime is 166316661349. The reversal of 166316661331 is 133166613661.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166316661331 is a prime.

It is a super-2 number, since 2×166316661331² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166316661311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83158330665 + 83158330666.

It is an arithmetic number, because the mean of its divisors is an integer number (83158330666).

Almost surely, 2^166316661331 is an apocalyptic number.

166316661331 is a deficient number, since it is larger than the sum of its proper divisors (1).

166316661331 is an equidigital number, since it uses as much as digits as its factorization.

166316661331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 43.

The spelling of 166316661331 in words is "one hundred sixty-six billion, three hundred sixteen million, six hundred sixty-one thousand, three hundred thirty-one".