21861976 has 16 divisors (see below), whose sum is σ = 41068440. Its totient is φ = 10910400.

The previous prime is 21861971. The next prime is 21861977. The reversal of 21861976 is 67916812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21861971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2535 + ... + 7081.

Almost surely, 2^21861976 is an apocalyptic number.

It is an amenable number.

21861976 is a deficient number, since it is larger than the sum of its proper divisors (19206464).

21861976 is a wasteful number, since it uses less digits than its factorization.

21861976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5154 (or 5150 counting only the distinct ones).

The product of its digits is 36288, while the sum is 40.

The square root of 21861976 is about 4675.6792019984. The cubic root of 21861976 is about 279.6167204831.

The spelling of 21861976 in words is "twenty-one million, eight hundred sixty-one thousand, nine hundred seventy-six".