21275255 has 8 divisors (see below), whose sum is σ = 26073792. Its totient is φ = 16657888.

The previous prime is 21275237. The next prime is 21275281. The reversal of 21275255 is 55257212.

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

It is a cyclic number.

It is not a de Polignac number, because 21275255 - 2⁸ = 21274999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45032 + ... + 45501.

It is an arithmetic number, because the mean of its divisors is an integer number (3259224).

Almost surely, 2^21275255 is an apocalyptic number.

21275255 is a deficient number, since it is larger than the sum of its proper divisors (4798537).

21275255 is an equidigital number, since it uses as much as digits as its factorization.

21275255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90585.

The product of its digits is 7000, while the sum is 29.

The square root of 21275255 is about 4612.5107045946. The cubic root of 21275255 is about 277.0925980784.

The spelling of 21275255 in words is "twenty-one million, two hundred seventy-five thousand, two hundred fifty-five".