181491852 has 18 divisors (see below), whose sum is σ = 423589908. Its totient is φ = 60481728.

The previous prime is 181491823. The next prime is 181491901. The reversal of 181491852 is 258194181.

It is a self number, because there is not a number n which added to its sum of digits gives 181491852.

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, 44724 + ... + 48612.

Almost surely, 2^181491852 is an apocalyptic number.

181491852 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

181491852 is an abundant number, since it is smaller than the sum of its proper divisors (242098056).

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

181491852 is an frugal number, since it uses more digits than its factorization.

181491852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7785 (or 3894 counting only the distinct ones).

The product of its digits is 23040, while the sum is 39.

The square root of 181491852 is about 13471.8911812707. The cubic root of 181491852 is about 566.1772014848.

The spelling of 181491852 in words is "one hundred eighty-one million, four hundred ninety-one thousand, eight hundred fifty-two".