21273263 has 8 divisors (see below), whose sum is σ = 23276160. Its totient is φ = 19281880.

The previous prime is 21273257. The next prime is 21273271. The reversal of 21273263 is 36237212.

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 21273263 - 2²² = 17078959 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21273253) 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 7 ways as a sum of consecutive naturals, for example, 1256 + ... + 6642.

It is an arithmetic number, because the mean of its divisors is an integer number (2909520).

Almost surely, 2^21273263 is an apocalyptic number.

21273263 is a deficient number, since it is larger than the sum of its proper divisors (2002897).

21273263 is a wasteful number, since it uses less digits than its factorization.

21273263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5757.

The product of its digits is 3024, while the sum is 26.

The square root of 21273263 is about 4612.2947650817. The cubic root of 21273263 is about 277.0839497577.

The spelling of 21273263 in words is "twenty-one million, two hundred seventy-three thousand, two hundred sixty-three".