21892210 has 8 divisors (see below), whose sum is σ = 39405996. Its totient is φ = 8756880.

The previous prime is 21892207. The next prime is 21892249. The reversal of 21892210 is 1229812.

It can be written as a sum of positive squares in 2 ways, for example, as 19722481 + 2169729 = 4441^2 + 1473^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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, 1094601 + ... + 1094620.

Almost surely, 2^21892210 is an apocalyptic number.

21892210 is a deficient number, since it is larger than the sum of its proper divisors (17513786).

21892210 is a wasteful number, since it uses less digits than its factorization.

21892210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2189228.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 21892210 is about 4678.9111981315. The cubic root of 21892210 is about 279.7455596725.

The spelling of 21892210 in words is "twenty-one million, eight hundred ninety-two thousand, two hundred ten".