21323512 has 16 divisors (see below), whose sum is σ = 45693360. Its totient is φ = 9138624.

The previous prime is 21323509. The next prime is 21323513. The reversal of 21323512 is 21532312.

It is a self number, because there is not a number n which added to its sum of digits gives 21323512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323513) 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, 190333 + ... + 190444.

It is an arithmetic number, because the mean of its divisors is an integer number (2855835).

Almost surely, 2^21323512 is an apocalyptic number.

It is an amenable number.

21323512 is an abundant number, since it is smaller than the sum of its proper divisors (24369848).

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

21323512 is a wasteful number, since it uses less digits than its factorization.

21323512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380790 (or 380786 counting only the distinct ones).

The product of its digits is 360, while the sum is 19.

The square root of 21323512 is about 4617.7388406015. The cubic root of 21323512 is about 277.3019423810.

Adding to 21323512 its reverse (21532312), we get a palindrome (42855824).

The spelling of 21323512 in words is "twenty-one million, three hundred twenty-three thousand, five hundred twelve".