21676872 has 64 divisors (see below), whose sum is σ = 65203200. Its totient is φ = 5866560.

The previous prime is 21676847. The next prime is 21676877. The reversal of 21676872 is 27867612.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21676872.

It is not an unprimeable number, because it can be changed into a prime (21676877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 204 + ... + 6587.

It is an arithmetic number, because the mean of its divisors is an integer number (1018800).

Almost surely, 2^21676872 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 21676872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32601600).

21676872 is an abundant number, since it is smaller than the sum of its proper divisors (43526328).

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

21676872 is a wasteful number, since it uses less digits than its factorization.

21676872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6826 (or 6822 counting only the distinct ones).

The product of its digits is 56448, while the sum is 39.

The square root of 21676872 is about 4655.8427808507. The cubic root of 21676872 is about 278.8253168422.

The spelling of 21676872 in words is "twenty-one million, six hundred seventy-six thousand, eight hundred seventy-two".