22721990 has 8 divisors (see below), whose sum is σ = 40899600. Its totient is φ = 9088792.

The previous prime is 22721989. The next prime is 22722023. The reversal of 22721990 is 9912722.

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

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, 1136090 + ... + 1136109.

It is an arithmetic number, because the mean of its divisors is an integer number (5112450).

Almost surely, 2^22721990 is an apocalyptic number.

22721990 is a deficient number, since it is larger than the sum of its proper divisors (18177610).

22721990 is a wasteful number, since it uses less digits than its factorization.

22721990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2272206.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 22721990 is about 4766.7588569173. The cubic root of 22721990 is about 283.2362189279.

The spelling of 22721990 in words is "twenty-two million, seven hundred twenty-one thousand, nine hundred ninety".