161665432 has 32 divisors (see below), whose sum is σ = 313463520. Its totient is φ = 78105600.

The previous prime is 161665429. The next prime is 161665481. The reversal of 161665432 is 234566161.

It is a super-2 number, since 2×161665432² = 52271423807493248, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42888 + ... + 46504.

It is an arithmetic number, because the mean of its divisors is an integer number (9795735).

Almost surely, 2^161665432 is an apocalyptic number.

It is an amenable number.

161665432 is a deficient number, since it is larger than the sum of its proper divisors (151798088).

161665432 is a wasteful number, since it uses less digits than its factorization.

161665432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3811 (or 3807 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 161665432 is about 12714.7721961504. The cubic root of 161665432 is about 544.7606411809.

The spelling of 161665432 in words is "one hundred sixty-one million, six hundred sixty-five thousand, four hundred thirty-two".