21289192 has 16 divisors (see below), whose sum is σ = 40025700. Its totient is φ = 10615680.

The previous prime is 21289189. The next prime is 21289201. The reversal of 21289192 is 29198212.

It can be written as a sum of positive squares in 2 ways, for example, as 21288996 + 196 = 4614^2 + 14^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309 + ... + 6532.

Almost surely, 2^21289192 is an apocalyptic number.

It is an amenable number.

21289192 is a deficient number, since it is larger than the sum of its proper divisors (18736508).

21289192 is a wasteful number, since it uses less digits than its factorization.

21289192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7236 (or 7232 counting only the distinct ones).

The product of its digits is 5184, while the sum is 34.

The square root of 21289192 is about 4614.0212396564. The cubic root of 21289192 is about 277.1530908367.

The spelling of 21289192 in words is "twenty-one million, two hundred eighty-nine thousand, one hundred ninety-two".