18581772 has 96 divisors (see below), whose sum is σ = 51609600. Its totient is φ = 5140800.

The previous prime is 18581749. The next prime is 18581777. The reversal of 18581772 is 27718581.

It is a self number, because there is not a number n which added to its sum of digits gives 18581772.

It is not an unprimeable number, because it can be changed into a prime (18581777) 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, 77629 + ... + 77867.

It is an arithmetic number, because the mean of its divisors is an integer number (537600).

Almost surely, 2^18581772 is an apocalyptic number.

18581772 is a gapful number since it is divisible by the number (12) 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 18581772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25804800).

18581772 is an abundant number, since it is smaller than the sum of its proper divisors (33027828).

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

18581772 is a wasteful number, since it uses less digits than its factorization.

18581772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307 (or 305 counting only the distinct ones).

The product of its digits is 31360, while the sum is 39.

The square root of 18581772 is about 4310.6579544195. The cubic root of 18581772 is about 264.8677256086.

The spelling of 18581772 in words is "eighteen million, five hundred eighty-one thousand, seven hundred seventy-two".