21822812 has 12 divisors (see below), whose sum is σ = 41661816. Its totient is φ = 9919440.

The previous prime is 21822809. The next prime is 21822841.

21822812 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 247943 + ... + 248030.

It is an arithmetic number, because the mean of its divisors is an integer number (3471818).

Almost surely, 2^21822812 is an apocalyptic number.

21822812 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21822812 is a deficient number, since it is larger than the sum of its proper divisors (19839004).

21822812 is a wasteful number, since it uses less digits than its factorization.

21822812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495988 (or 495986 counting only the distinct ones).

The product of its digits is 1024, while the sum is 26.

The square root of 21822812 is about 4671.4892700294. The cubic root of 21822812 is about 279.4496502697.

It can be divided in two parts, 2182 and 2812, that added together give a palindrome (4994).

The spelling of 21822812 in words is "twenty-one million, eight hundred twenty-two thousand, eight hundred twelve".