181381356 has 60 divisors (see below), whose sum is σ = 510652912. Its totient is φ = 55808352.

The previous prime is 181381349. The next prime is 181381373. The reversal of 181381356 is 653183181.

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

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 181381356.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 17320 + ... + 25743.

Almost surely, 2^181381356 is an apocalyptic number.

It is an amenable number.

181381356 is an abundant number, since it is smaller than the sum of its proper divisors (329271556).

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

181381356 is a wasteful number, since it uses less digits than its factorization.

181381356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43092 (or 43081 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 181381356 is about 13467.7895736457. The cubic root of 181381356 is about 566.0622780219.

The spelling of 181381356 in words is "one hundred eighty-one million, three hundred eighty-one thousand, three hundred fifty-six".