21358275 has 12 divisors (see below), whose sum is σ = 35312472. Its totient is φ = 11391040.

The previous prime is 21358247. The next prime is 21358277. The reversal of 21358275 is 57285312.

It is not a de Polignac number, because 21358275 - 2⁸ = 21358019 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21358277) 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 11 ways as a sum of consecutive naturals, for example, 142314 + ... + 142463.

It is an arithmetic number, because the mean of its divisors is an integer number (2942706).

Almost surely, 2^21358275 is an apocalyptic number.

21358275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21358275 is a deficient number, since it is larger than the sum of its proper divisors (13954197).

21358275 is a wasteful number, since it uses less digits than its factorization.

21358275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284790 (or 284785 counting only the distinct ones).

The product of its digits is 16800, while the sum is 33.

The square root of 21358275 is about 4621.5013794221. The cubic root of 21358275 is about 277.4525525566.

The spelling of 21358275 in words is "twenty-one million, three hundred fifty-eight thousand, two hundred seventy-five".