161551916 has 24 divisors (see below), whose sum is σ = 292482960. Its totient is φ = 78017472.

The previous prime is 161551913. The next prime is 161551921. The reversal of 161551916 is 619155161.

It is not an unprimeable number, because it can be changed into a prime (161551913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16646 + ... + 24498.

It is an arithmetic number, because the mean of its divisors is an integer number (12186790).

Almost surely, 2^161551916 is an apocalyptic number.

It is an amenable number.

161551916 is a deficient number, since it is larger than the sum of its proper divisors (130931044).

161551916 is a wasteful number, since it uses less digits than its factorization.

161551916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8033 (or 8031 counting only the distinct ones).

The product of its digits is 8100, while the sum is 35.

The square root of 161551916 is about 12710.3074707105. The cubic root of 161551916 is about 544.6331071587.

The spelling of 161551916 in words is "one hundred sixty-one million, five hundred fifty-one thousand, nine hundred sixteen".