161155656 has 128 divisors (see below), whose sum is σ = 463660800. Its totient is φ = 52488000.

The previous prime is 161155613. The next prime is 161155679. The reversal of 161155656 is 656551161.

It is a super-2 number, since 2×161155656² = 51942290921580672, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 161155656.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 1067181 + ... + 1067331.

It is an arithmetic number, because the mean of its divisors is an integer number (3622350).

Almost surely, 2^161155656 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 161155656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (231830400).

161155656 is an abundant number, since it is smaller than the sum of its proper divisors (302505144).

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

161155656 is an equidigital number, since it uses as much as digits as its factorization.

161155656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239 (or 217 counting only the distinct ones).

The product of its digits is 27000, while the sum is 36.

The square root of 161155656 is about 12694.7097643073. The cubic root of 161155656 is about 544.1874444164.

The spelling of 161155656 in words is "one hundred sixty-one million, one hundred fifty-five thousand, six hundred fifty-six".