21851622 has 24 divisors (see below), whose sum is σ = 50987664. Its totient is φ = 6723504.

The previous prime is 21851597. The next prime is 21851623. The reversal of 21851622 is 22615812.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21851623) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 46458 + ... + 46925.

It is an arithmetic number, because the mean of its divisors is an integer number (2124486).

Almost surely, 2^21851622 is an apocalyptic number.

21851622 is an abundant number, since it is smaller than the sum of its proper divisors (29136042).

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

21851622 is a wasteful number, since it uses less digits than its factorization.

21851622 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93404 (or 93401 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 21851622 is about 4674.5718520523. The cubic root of 21851622 is about 279.5725706359.

The spelling of 21851622 in words is "twenty-one million, eight hundred fifty-one thousand, six hundred twenty-two".