21606876 has 72 divisors (see below), whose sum is σ = 59404800. Its totient is φ = 6596640.

The previous prime is 21606869. The next prime is 21606899. The reversal of 21606876 is 67860612.

It is a happy number.

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 21606876.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20695 + ... + 21713.

Almost surely, 2^21606876 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 21606876, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29702400).

21606876 is an abundant number, since it is smaller than the sum of its proper divisors (37797924).

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

21606876 is a wasteful number, since it uses less digits than its factorization.

21606876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1079 (or 1074 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 21606876 is about 4648.3196964064. The cubic root of 21606876 is about 278.5248783305.

The spelling of 21606876 in words is "twenty-one million, six hundred six thousand, eight hundred seventy-six".