20936181 has 24 divisors (see below), whose sum is σ = 32934144. Its totient is φ = 11793600.

The previous prime is 20936177. The next prime is 20936183. The reversal of 20936181 is 18163902.

It is not a de Polignac number, because 20936181 - 2² = 20936177 is a prime.

It is a super-2 number, since 2×20936181² = 876647349729522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20936183) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9756 + ... + 11706.

It is an arithmetic number, because the mean of its divisors is an integer number (1372256).

Almost surely, 2^20936181 is an apocalyptic number.

20936181 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20936181 is a deficient number, since it is larger than the sum of its proper divisors (11997963).

20936181 is a wasteful number, since it uses less digits than its factorization.

20936181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2041 (or 2034 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 20936181 is about 4575.6071728242. The cubic root of 20936181 is about 275.6126550278.

The spelling of 20936181 in words is "twenty million, nine hundred thirty-six thousand, one hundred eighty-one".