165971313179557 has 4 divisors (see below), whose sum is σ = 166423551090496. Its totient is φ = 165519075268620.

The previous prime is 165971313179527. The next prime is 165971313179561. The reversal of 165971313179557 is 755971313179561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 165971313179557 - 2⁷ = 165971313179429 is a prime.

It is a super-2 number, since 2×165971313179557² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165971313179527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226118954919 + ... + 226118955652.

It is an arithmetic number, because the mean of its divisors is an integer number (41605887772624).

Almost surely, 2^{165971313179557} is an apocalyptic number.

It is an amenable number.

165971313179557 is a deficient number, since it is larger than the sum of its proper divisors (452237910939).

165971313179557 is an equidigital number, since it uses as much as digits as its factorization.

165971313179557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452237910938.

The product of its digits is 187535250, while the sum is 70.

The spelling of 165971313179557 in words is "one hundred sixty-five trillion, nine hundred seventy-one billion, three hundred thirteen million, one hundred seventy-nine thousand, five hundred fifty-seven".