21268875 has 32 divisors (see below), whose sum is σ = 36241920. Its totient is φ = 11071200.

The previous prime is 21268867. The next prime is 21268879. The reversal of 21268875 is 57886212.

It is not a de Polignac number, because 21268875 - 2³ = 21268867 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21268879) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15466 + ... + 16784.

It is an arithmetic number, because the mean of its divisors is an integer number (1132560).

Almost surely, 2^21268875 is an apocalyptic number.

21268875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21268875 is a deficient number, since it is larger than the sum of its proper divisors (14973045).

21268875 is a wasteful number, since it uses less digits than its factorization.

21268875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1380 (or 1370 counting only the distinct ones).

The product of its digits is 53760, while the sum is 39.

The square root of 21268875 is about 4611.8190554270. The cubic root of 21268875 is about 277.0648972351.

The spelling of 21268875 in words is "twenty-one million, two hundred sixty-eight thousand, eight hundred seventy-five".