19981136 has 20 divisors (see below), whose sum is σ = 44244192. Its totient is φ = 8563296.

The previous prime is 19981109. The next prime is 19981139. The reversal of 19981136 is 63118991.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 19981136.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19981139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89090 + ... + 89313.

Almost surely, 2^19981136 is an apocalyptic number.

19981136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

19981136 is an abundant number, since it is smaller than the sum of its proper divisors (24263056).

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

19981136 is a wasteful number, since it uses less digits than its factorization.

19981136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178418 (or 178412 counting only the distinct ones).

The product of its digits is 11664, while the sum is 38.

The square root of 19981136 is about 4470.0263981323. The cubic root of 19981136 is about 271.3563935243.

The spelling of 19981136 in words is "nineteen million, nine hundred eighty-one thousand, one hundred thirty-six".