21010768 has 20 divisors (see below), whose sum is σ = 41072148. Its totient is φ = 10411520.

The previous prime is 21010763. The next prime is 21010811. The reversal of 21010768 is 86701012.

It can be written as a sum of positive squares in 2 ways, for example, as 868624 + 20142144 = 932^2 + 4488^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010763) 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, 4003 + ... + 7618.

Almost surely, 2^21010768 is an apocalyptic number.

It is an amenable number.

21010768 is a deficient number, since it is larger than the sum of its proper divisors (20061380).

21010768 is a wasteful number, since it uses less digits than its factorization.

21010768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11742 (or 11736 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 21010768 is about 4583.7504295064. The cubic root of 21010768 is about 275.9395652877.

The spelling of 21010768 in words is "twenty-one million, ten thousand, seven hundred sixty-eight".