21945698 has 16 divisors (see below), whose sum is σ = 33790176. Its totient is φ = 10686240.

The previous prime is 21945689. The next prime is 21945751. The reversal of 21945698 is 89654912.

It is a super-2 number, since 2×21945698² = 963227321414408, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11213 + ... + 13023.

It is an arithmetic number, because the mean of its divisors is an integer number (2111886).

Almost surely, 2^21945698 is an apocalyptic number.

21945698 is a deficient number, since it is larger than the sum of its proper divisors (11844478).

21945698 is a wasteful number, since it uses less digits than its factorization.

21945698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1969.

The product of its digits is 155520, while the sum is 44.

The square root of 21945698 is about 4684.6235707899. The cubic root of 21945698 is about 279.9732032179.

The spelling of 21945698 in words is "twenty-one million, nine hundred forty-five thousand, six hundred ninety-eight".