21112936 has 32 divisors (see below), whose sum is σ = 43129800. Its totient is φ = 9630720.

The previous prime is 21112913. The next prime is 21112951. The reversal of 21112936 is 63921112.

It can be written as a sum of positive squares in 4 ways, for example, as 12292036 + 8820900 = 3506^2 + 2970^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21112936.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8116 + ... + 10396.

Almost surely, 2^21112936 is an apocalyptic number.

21112936 is a gapful number since it is divisible by the number (26) 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 21112936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21564900).

21112936 is an abundant number, since it is smaller than the sum of its proper divisors (22016864).

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

21112936 is a wasteful number, since it uses less digits than its factorization.

21112936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2389 (or 2385 counting only the distinct ones).

The product of its digits is 648, while the sum is 25.

The square root of 21112936 is about 4594.8815001042. The cubic root of 21112936 is about 276.3861080684.

The spelling of 21112936 in words is "twenty-one million, one hundred twelve thousand, nine hundred thirty-six".