21889995 has 32 divisors (see below), whose sum is σ = 37324800. Its totient is φ = 10923264.

The previous prime is 21889993. The next prime is 21890047. The reversal of 21889995 is 59998812.

It is not a de Polignac number, because 21889995 - 2¹ = 21889993 is a prime.

It is a super-2 number, since 2×21889995² = 958343762200050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21889991) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24934 + ... + 25796.

It is an arithmetic number, because the mean of its divisors is an integer number (1166400).

Almost surely, 2^21889995 is an apocalyptic number.

21889995 is a deficient number, since it is larger than the sum of its proper divisors (15434805).

21889995 is a wasteful number, since it uses less digits than its factorization.

21889995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 979.

The product of its digits is 466560, while the sum is 51.

The square root of 21889995 is about 4678.6744917765. The cubic root of 21889995 is about 279.7361246982.

The spelling of 21889995 in words is "twenty-one million, eight hundred eighty-nine thousand, nine hundred ninety-five".