21866376 has 64 divisors (see below), whose sum is σ = 65203200. Its totient is φ = 5974848.

The previous prime is 21866333. The next prime is 21866387. The reversal of 21866376 is 67366812.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1035 + ... + 6693.

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

Almost surely, 2^21866376 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 21866376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32601600).

21866376 is an abundant number, since it is smaller than the sum of its proper divisors (43336824).

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

21866376 is a wasteful number, since it uses less digits than its factorization.

21866376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5698 (or 5694 counting only the distinct ones).

The product of its digits is 72576, while the sum is 39.

The square root of 21866376 is about 4676.1496982026. The cubic root of 21866376 is about 279.6354780288.

The spelling of 21866376 in words is "twenty-one million, eight hundred sixty-six thousand, three hundred seventy-six".