21366716 has 24 divisors (see below), whose sum is σ = 44983680. Its totient is φ = 8674992.

The previous prime is 21366713. The next prime is 21366721. The reversal of 21366716 is 61766312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21366713) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19550 + ... + 20613.

It is an arithmetic number, because the mean of its divisors is an integer number (1874320).

Almost surely, 2^21366716 is an apocalyptic number.

It is an amenable number.

21366716 is an abundant number, since it is smaller than the sum of its proper divisors (23616964).

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

21366716 is a wasteful number, since it uses less digits than its factorization.

21366716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40193 (or 40191 counting only the distinct ones).

The product of its digits is 9072, while the sum is 32.

The square root of 21366716 is about 4622.4145205726. The cubic root of 21366716 is about 277.4890984003.

The spelling of 21366716 in words is "twenty-one million, three hundred sixty-six thousand, seven hundred sixteen".