161728724 has 12 divisors (see below), whose sum is σ = 285062400. Its totient is φ = 80282328.

The previous prime is 161728717. The next prime is 161728733. The reversal of 161728724 is 427827161.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144884 + ... + 145995.

It is an arithmetic number, because the mean of its divisors is an integer number (23755200).

Almost surely, 2^161728724 is an apocalyptic number.

It is an amenable number.

161728724 is a deficient number, since it is larger than the sum of its proper divisors (123333676).

161728724 is a wasteful number, since it uses less digits than its factorization.

161728724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291022 (or 291020 counting only the distinct ones).

The product of its digits is 37632, while the sum is 38.

The square root of 161728724 is about 12717.2608685990. The cubic root of 161728724 is about 544.8317231505.

The spelling of 161728724 in words is "one hundred sixty-one million, seven hundred twenty-eight thousand, seven hundred twenty-four".