161455590 has 48 divisors (see below), whose sum is σ = 423884448. Its totient is φ = 42634368.

The previous prime is 161455573. The next prime is 161455601. The reversal of 161455590 is 95554161.

161455590 is a `hidden beast` number, since 1 + 6 + 14 + 55 + 590 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 562 + ... + 17978.

It is an arithmetic number, because the mean of its divisors is an integer number (8830926).

Almost surely, 2^161455590 is an apocalyptic number.

161455590 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 161455590, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211942224).

161455590 is an abundant number, since it is smaller than the sum of its proper divisors (262428858).

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

161455590 is a wasteful number, since it uses less digits than its factorization.

161455590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17533 (or 17530 counting only the distinct ones).

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

The square root of 161455590 is about 12706.5176189230. The cubic root of 161455590 is about 544.5248390544.

The spelling of 161455590 in words is "one hundred sixty-one million, four hundred fifty-five thousand, five hundred ninety".