161691532 has 6 divisors (see below), whose sum is σ = 282960188. Its totient is φ = 80845764.

The previous prime is 161691529. The next prime is 161691533. The reversal of 161691532 is 235196161.

161691532 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161691532² = 52288303041014048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161691533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20211438 + ... + 20211445.

Almost surely, 2^161691532 is an apocalyptic number.

It is an amenable number.

161691532 is a deficient number, since it is larger than the sum of its proper divisors (121268656).

161691532 is a wasteful number, since it uses less digits than its factorization.

161691532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40422887 (or 40422885 counting only the distinct ones).

The product of its digits is 9720, while the sum is 34.

The square root of 161691532 is about 12715.7985199515. The cubic root of 161691532 is about 544.7899558123.

The spelling of 161691532 in words is "one hundred sixty-one million, six hundred ninety-one thousand, five hundred thirty-two".