166195055639 has 2 divisors, whose sum is σ = 166195055640. Its totient is φ = 166195055638.

The previous prime is 166195055531. The next prime is 166195055687. The reversal of 166195055639 is 936550591661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166195055639 - 2²⁴ = 166178278423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166195055239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83097527819 + 83097527820.

It is an arithmetic number, because the mean of its divisors is an integer number (83097527820).

Almost surely, 2^166195055639 is an apocalyptic number.

166195055639 is a deficient number, since it is larger than the sum of its proper divisors (1).

166195055639 is an equidigital number, since it uses as much as digits as its factorization.

166195055639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561000, while the sum is 56.

The spelling of 166195055639 in words is "one hundred sixty-six billion, one hundred ninety-five million, fifty-five thousand, six hundred thirty-nine".