161431901889 has 16 divisors (see below), whose sum is σ = 227764306944. Its totient is φ = 101492190800.

The previous prime is 161431901879. The next prime is 161431901909. The reversal of 161431901889 is 988109134161.

It is a cyclic number.

It is not a de Polignac number, because 161431901889 - 2⁸ = 161431901633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161431901809) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16471107 + ... + 16480904.

It is an arithmetic number, because the mean of its divisors is an integer number (14235269184).

Almost surely, 2^161431901889 is an apocalyptic number.

It is an amenable number.

161431901889 is a deficient number, since it is larger than the sum of its proper divisors (66332405055).

161431901889 is a wasteful number, since it uses less digits than its factorization.

161431901889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32952108.

The product of its (nonzero) digits is 373248, while the sum is 51.

The spelling of 161431901889 in words is "one hundred sixty-one billion, four hundred thirty-one million, nine hundred one thousand, eight hundred eighty-nine".