21868370 has 8 divisors (see below), whose sum is σ = 39363084. Its totient is φ = 8747344.

The previous prime is 21868367. The next prime is 21868393. The reversal of 21868370 is 7386812.

It can be written as a sum of positive squares in 2 ways, for example, as 20620681 + 1247689 = 4541^2 + 1117^2 .

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21868370.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1093409 + ... + 1093428.

Almost surely, 2^21868370 is an apocalyptic number.

21868370 is a deficient number, since it is larger than the sum of its proper divisors (17494714).

21868370 is a wasteful number, since it uses less digits than its factorization.

21868370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2186844.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 21868370 is about 4676.3629029407. The cubic root of 21868370 is about 279.6439777789.

The spelling of 21868370 in words is "twenty-one million, eight hundred sixty-eight thousand, three hundred seventy".