21791622 has 8 divisors (see below), whose sum is σ = 43583256. Its totient is φ = 7263872.

The previous prime is 21791617. The next prime is 21791629. The reversal of 21791622 is 22619712.

It is a sphenic number, since it is the product of 3 distinct primes.

21791622 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 21791622.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21791629) 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, 1815963 + ... + 1815974.

It is an arithmetic number, because the mean of its divisors is an integer number (5447907).

Almost surely, 2^21791622 is an apocalyptic number.

21791622 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21791622 is a wasteful number, since it uses less digits than its factorization.

21791622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3631942.

The product of its digits is 3024, while the sum is 30.

The square root of 21791622 is about 4668.1497405289. The cubic root of 21791622 is about 279.3164534064.

The spelling of 21791622 in words is "twenty-one million, seven hundred ninety-one thousand, six hundred twenty-two".