161561088 has 320 divisors, whose sum is σ = 549964800. Its totient is φ = 46448640.

The previous prime is 161561087. The next prime is 161561089. The reversal of 161561088 is 880165161.

161561088 is a `hidden beast` number, since 16 + 1 + 561 + 0 + 88 = 666.

It is an interprime number because it is at equal distance from previous prime (161561087) and next prime (161561089).

It is a super-2 number, since 2×161561088² = 52203970311487488, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (161561087) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5211633 + ... + 5211663.

It is an arithmetic number, because the mean of its divisors is an integer number (1718640).

Almost surely, 2^161561088 is an apocalyptic number.

161561088 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161561088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274982400).

161561088 is an abundant number, since it is smaller than the sum of its proper divisors (388403712).

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

161561088 is a wasteful number, since it uses less digits than its factorization.

161561088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 161561088 is about 12710.6682751144. The cubic root of 161561088 is about 544.6434140216.

The spelling of 161561088 in words is "one hundred sixty-one million, five hundred sixty-one thousand, eighty-eight".