21164716 has 12 divisors (see below), whose sum is σ = 37666440. Its totient is φ = 10402880.

The previous prime is 21164713. The next prime is 21164771. The reversal of 21164716 is 61746112.

21164716 = 254² + 255² + ... + 430².

It is not an unprimeable number, because it can be changed into a prime (21164713) 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, 44605 + ... + 45076.

It is an arithmetic number, because the mean of its divisors is an integer number (3138870).

Almost surely, 2^21164716 is an apocalyptic number.

It is an amenable number.

21164716 is a deficient number, since it is larger than the sum of its proper divisors (16501724).

21164716 is a wasteful number, since it uses less digits than its factorization.

21164716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89744 (or 89742 counting only the distinct ones).

The product of its digits is 2016, while the sum is 28.

The square root of 21164716 is about 4600.5125801371. The cubic root of 21164716 is about 276.6118715373.

The spelling of 21164716 in words is "twenty-one million, one hundred sixty-four thousand, seven hundred sixteen".