161566616115957 has 32 divisors (see below), whose sum is σ = 236752178140800. Its totient is φ = 97392061907712.

The previous prime is 161566616115953. The next prime is 161566616115979. The reversal of 161566616115957 is 759511616665161.

It is not a de Polignac number, because 161566616115957 - 2² = 161566616115953 is a prime.

It is a super-2 number, since 2×161566616115957² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161566616115953) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61858482 + ... + 64417427.

It is an arithmetic number, because the mean of its divisors is an integer number (7398505566900).

Almost surely, 2^{161566616115957} is an apocalyptic number.

It is an amenable number.

161566616115957 is a deficient number, since it is larger than the sum of its proper divisors (75185562024843).

161566616115957 is a wasteful number, since it uses less digits than its factorization.

161566616115957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126276597.

The product of its digits is 61236000, while the sum is 66.

The spelling of 161566616115957 in words is "one hundred sixty-one trillion, five hundred sixty-six billion, six hundred sixteen million, one hundred fifteen thousand, nine hundred fifty-seven".