21995199 has 16 divisors (see below), whose sum is σ = 34003200. Its totient is φ = 14025528.

The previous prime is 21995189. The next prime is 21995203. The reversal of 21995199 is 99159912.

It is not a de Polignac number, because 21995199 - 2⁵ = 21995167 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21995189) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17089 + ... + 18330.

It is an arithmetic number, because the mean of its divisors is an integer number (2125200).

Almost surely, 2^21995199 is an apocalyptic number.

21995199 is a deficient number, since it is larger than the sum of its proper divisors (12008001).

21995199 is a wasteful number, since it uses less digits than its factorization.

21995199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35451 (or 35445 counting only the distinct ones).

The product of its digits is 65610, while the sum is 45.

The square root of 21995199 is about 4689.9039435792. The cubic root of 21995199 is about 280.1835488693.

The spelling of 21995199 in words is "twenty-one million, nine hundred ninety-five thousand, one hundred ninety-nine".