161354612691 has 18 divisors (see below), whose sum is σ = 233558350220. Its totient is φ = 107343796536.

The previous prime is 161354612687. The next prime is 161354612701. The reversal of 161354612691 is 196216453161.

161354612691 is a `hidden beast` number, since 1 + 6 + 1 + 3 + 546 + 12 + 6 + 91 = 666.

It is not a de Polignac number, because 161354612691 - 2² = 161354612687 is a prime.

It is a super-2 number, since 2×161354612691² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161354612681) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2025900 + ... + 2104038.

Almost surely, 2^161354612691 is an apocalyptic number.

161354612691 is a deficient number, since it is larger than the sum of its proper divisors (72203737529).

161354612691 is an frugal number, since it uses more digits than its factorization.

161354612691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79103 (or 78621 counting only the distinct ones).

The product of its digits is 233280, while the sum is 45.

The spelling of 161354612691 in words is "one hundred sixty-one billion, three hundred fifty-four million, six hundred twelve thousand, six hundred ninety-one".