166558534631 has 2 divisors, whose sum is σ = 166558534632. Its totient is φ = 166558534630.

The previous prime is 166558534613. The next prime is 166558534643. The reversal of 166558534631 is 136435855661.

Together with previous prime (166558534613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166558534631 - 2¹⁰ = 166558533607 is a prime.

It is a super-2 number, since 2×166558534631² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166558504631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83279267315 + 83279267316.

It is an arithmetic number, because the mean of its divisors is an integer number (83279267316).

Almost surely, 2^166558534631 is an apocalyptic number.

166558534631 is a deficient number, since it is larger than the sum of its proper divisors (1).

166558534631 is an equidigital number, since it uses as much as digits as its factorization.

166558534631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776000, while the sum is 53.

The spelling of 166558534631 in words is "one hundred sixty-six billion, five hundred fifty-eight million, five hundred thirty-four thousand, six hundred thirty-one".