161975198605 has 24 divisors (see below), whose sum is σ = 214229062656. Its totient is φ = 117479002080.

The previous prime is 161975198579. The next prime is 161975198647. The reversal of 161975198605 is 506891579161.

It is not a de Polignac number, because 161975198605 - 2⁵ = 161975198573 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161975198605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 142717 + ... + 586786.

It is an arithmetic number, because the mean of its divisors is an integer number (8926210944).

Almost surely, 2^161975198605 is an apocalyptic number.

It is an amenable number.

161975198605 is a deficient number, since it is larger than the sum of its proper divisors (52253864051).

161975198605 is a wasteful number, since it uses less digits than its factorization.

161975198605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729897 (or 729886 counting only the distinct ones).

The product of its (nonzero) digits is 4082400, while the sum is 58.

The spelling of 161975198605 in words is "one hundred sixty-one billion, nine hundred seventy-five million, one hundred ninety-eight thousand, six hundred five".