21895966 has 16 divisors (see below), whose sum is σ = 34941456. Its totient is φ = 10254976.

The previous prime is 21895933. The next prime is 21895969. The reversal of 21895966 is 66959812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21895969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6300 + ... + 9136.

It is an arithmetic number, because the mean of its divisors is an integer number (2183841).

Almost surely, 2^21895966 is an apocalyptic number.

21895966 is a deficient number, since it is larger than the sum of its proper divisors (13045490).

21895966 is a wasteful number, since it uses less digits than its factorization.

21895966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3083.

The product of its digits is 233280, while the sum is 46.

The square root of 21895966 is about 4679.3125563484. The cubic root of 21895966 is about 279.7615572083.

The spelling of 21895966 in words is "twenty-one million, eight hundred ninety-five thousand, nine hundred sixty-six".