161556332 has 72 divisors (see below), whose sum is σ = 348662160. Its totient is φ = 65197440.

The previous prime is 161556331. The next prime is 161556377. The reversal of 161556332 is 233655161.

It is a super-2 number, since 2×161556332² = 52200896818588448, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161556331) 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 23 ways as a sum of consecutive naturals, for example, 244082 + ... + 244742.

It is an arithmetic number, because the mean of its divisors is an integer number (4842530).

Almost surely, 2^161556332 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161556332, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (174331080).

161556332 is an abundant number, since it is smaller than the sum of its proper divisors (187105828).

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

161556332 is a wasteful number, since it uses less digits than its factorization.

161556332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 751 (or 742 counting only the distinct ones).

The product of its digits is 16200, while the sum is 32.

The square root of 161556332 is about 12710.4811868001. The cubic root of 161556332 is about 544.6380696045.

The spelling of 161556332 in words is "one hundred sixty-one million, five hundred fifty-six thousand, three hundred thirty-two".