21273055 has 12 divisors (see below), whose sum is σ = 26175816. Its totient is φ = 16596800.

The previous prime is 21273023. The next prime is 21273061. The reversal of 21273055 is 55037212.

It is not a de Polignac number, because 21273055 - 2⁵ = 21273023 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7140 + ... + 9670.

It is an arithmetic number, because the mean of its divisors is an integer number (2181318).

Almost surely, 2^21273055 is an apocalyptic number.

21273055 is a deficient number, since it is larger than the sum of its proper divisors (4902761).

21273055 is an equidigital number, since it uses as much as digits as its factorization.

21273055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2618 (or 2577 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 21273055 is about 4612.2722165978. The cubic root of 21273055 is about 277.0830466891.

The spelling of 21273055 in words is "twenty-one million, two hundred seventy-three thousand, fifty-five".