161518356 has 18 divisors (see below), whose sum is σ = 408282602. Its totient is φ = 53839440.

The previous prime is 161518349. The next prime is 161518361. The reversal of 161518356 is 653815161.

161518356 is a `hidden beast` number, since 1 + 615 + 1 + 8 + 35 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 110880900 + 50637456 = 10530^2 + 7116^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 4486621 = 161518356 / (1 + 6 + 1 + 5 + 1 + 8 + 3 + 5 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 161518356.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2243275 + ... + 2243346.

Almost surely, 2^161518356 is an apocalyptic number.

It is an amenable number.

161518356 is an abundant number, since it is smaller than the sum of its proper divisors (246764246).

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

161518356 is a wasteful number, since it uses less digits than its factorization.

161518356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4486631 (or 4486626 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 161518356 is about 12708.9872137791. The cubic root of 161518356 is about 544.5953914132.

The spelling of 161518356 in words is "one hundred sixty-one million, five hundred eighteen thousand, three hundred fifty-six".