21312762 has 16 divisors (see below), whose sum is σ = 42677280. Its totient is φ = 7095632.

The previous prime is 21312751. The next prime is 21312763. The reversal of 21312762 is 26721312.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21312763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5053 + ... + 8255.

It is an arithmetic number, because the mean of its divisors is an integer number (2667330).

Almost surely, 2^21312762 is an apocalyptic number.

21312762 is an abundant number, since it is smaller than the sum of its proper divisors (21364518).

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

21312762 is a wasteful number, since it uses less digits than its factorization.

21312762 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4317.

The product of its digits is 1008, while the sum is 24.

The square root of 21312762 is about 4616.5747042586. The cubic root of 21312762 is about 277.2553350341.

The spelling of 21312762 in words is "twenty-one million, three hundred twelve thousand, seven hundred sixty-two".