21113976 has 128 divisors (see below), whose sum is σ = 61286400. Its totient is φ = 6013440.

The previous prime is 21113971. The next prime is 21113987. The reversal of 21113976 is 67931112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113971) 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, 357835 + ... + 357893.

It is an arithmetic number, because the mean of its divisors is an integer number (478800).

Almost surely, 2^21113976 is an apocalyptic number.

21113976 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 21113976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30643200).

21113976 is an abundant number, since it is smaller than the sum of its proper divisors (40172424).

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

21113976 is a wasteful number, since it uses less digits than its factorization.

21113976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149 (or 145 counting only the distinct ones).

The product of its digits is 2268, while the sum is 30.

The square root of 21113976 is about 4594.9946681144. The cubic root of 21113976 is about 276.3906461525.

The spelling of 21113976 in words is "twenty-one million, one hundred thirteen thousand, nine hundred seventy-six".