161520172 has 48 divisors (see below), whose sum is σ = 315705600. Its totient is φ = 71691200.

The previous prime is 161520157. The next prime is 161520173. The reversal of 161520172 is 271025161.

It is not an unprimeable number, because it can be changed into a prime (161520173) 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 15 ways as a sum of consecutive naturals, for example, 465303 + ... + 465649.

It is an arithmetic number, because the mean of its divisors is an integer number (6577200).

Almost surely, 2^161520172 is an apocalyptic number.

It is an amenable number.

161520172 is a deficient number, since it is larger than the sum of its proper divisors (154185428).

161520172 is a wasteful number, since it uses less digits than its factorization.

161520172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582 (or 580 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 161520172 is about 12709.0586590825. The cubic root of 161520172 is about 544.5974324227.

The spelling of 161520172 in words is "one hundred sixty-one million, five hundred twenty thousand, one hundred seventy-two".