21812468 has 24 divisors (see below), whose sum is σ = 40158720. Its totient is φ = 10352160.

The previous prime is 21812467. The next prime is 21812471. The reversal of 21812468 is 86421812.

It is a happy number.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21812467) 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, 4913 + ... + 8231.

It is an arithmetic number, because the mean of its divisors is an integer number (1673280).

Almost surely, 2^21812468 is an apocalyptic number.

It is an amenable number.

21812468 is a deficient number, since it is larger than the sum of its proper divisors (18346252).

21812468 is a wasteful number, since it uses less digits than its factorization.

21812468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3407 (or 3405 counting only the distinct ones).

The product of its digits is 6144, while the sum is 32.

The square root of 21812468 is about 4670.3819972246. The cubic root of 21812468 is about 279.4054903020.

The spelling of 21812468 in words is "twenty-one million, eight hundred twelve thousand, four hundred sixty-eight".