161865472 has 36 divisors (see below), whose sum is σ = 334255320. Its totient is φ = 78138368.

The previous prime is 161865463. The next prime is 161865479. The reversal of 161865472 is 274568161.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161865479) by changing a digit.

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, 3478 + ... + 18325.

It is an arithmetic number, because the mean of its divisors is an integer number (9284870).

Almost surely, 2^161865472 is an apocalyptic number.

It is an amenable number.

161865472 is an abundant number, since it is smaller than the sum of its proper divisors (172389848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161865472 is an equidigital number, since it uses as much as digits as its factorization.

161865472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21848 (or 21834 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 161865472 is about 12722.6362048123. The cubic root of 161865472 is about 544.9852387776.

The spelling of 161865472 in words is "one hundred sixty-one million, eight hundred sixty-five thousand, four hundred seventy-two".