166506631 has 2 divisors, whose sum is σ = 166506632. Its totient is φ = 166506630.

The previous prime is 166506589. The next prime is 166506647. The reversal of 166506631 is 136605661.

166506631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (136605661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166506631 - 2¹³ = 166498439 is a prime.

It is a super-2 number, since 2×166506631² = 55448916333940322, which contains 22 as substring.

It is equal to p_9318526 and since 166506631 and 9318526 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166506331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83253315 + 83253316.

It is an arithmetic number, because the mean of its divisors is an integer number (83253316).

Almost surely, 2^166506631 is an apocalyptic number.

166506631 is a deficient number, since it is larger than the sum of its proper divisors (1).

166506631 is an equidigital number, since it uses as much as digits as its factorization.

166506631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 166506631 is about 12903.7448440366. The cubic root of 166506631 is about 550.1450096981.

The spelling of 166506631 in words is "one hundred sixty-six million, five hundred six thousand, six hundred thirty-one".