21326976 has 240 divisors, whose sum is σ = 73866870. Its totient is φ = 6082560.

The previous prime is 21326953. The next prime is 21326989. The reversal of 21326976 is 67962312.

21326976 = 55³ + 56³ + ... + 98³.

It can be written as a sum of positive squares in only one way, i.e., 15681600 + 5645376 = 3960^2 + 2376^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21326976.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1254520 + ... + 1254536.

Almost surely, 2^21326976 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21326976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36933435).

21326976 is an abundant number, since it is smaller than the sum of its proper divisors (52539894).

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

21326976 is a wasteful number, since it uses less digits than its factorization.

21326976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65 (or 33 counting only the distinct ones).

The product of its digits is 27216, while the sum is 36.

The square root of 21326976 is about 4618.1139007175. The cubic root of 21326976 is about 277.3169574486.

21326976 divided by its sum of digits (36) gives a triangular number (592416 = T₁₀₈₈).

The spelling of 21326976 in words is "twenty-one million, three hundred twenty-six thousand, nine hundred seventy-six".