21273279 has 8 divisors (see below), whose sum is σ = 28387632. Its totient is φ = 14170560.

The previous prime is 21273277. The next prime is 21273283. The reversal of 21273279 is 97237212.

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

It is not a de Polignac number, because 21273279 - 2¹ = 21273277 is a prime.

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 (21273271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3187 + ... + 7259.

It is an arithmetic number, because the mean of its divisors is an integer number (3548454).

Almost surely, 2^21273279 is an apocalyptic number.

21273279 is a deficient number, since it is larger than the sum of its proper divisors (7114353).

21273279 is a wasteful number, since it uses less digits than its factorization.

21273279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5817.

The product of its digits is 10584, while the sum is 33.

The square root of 21273279 is about 4612.2964995759. The cubic root of 21273279 is about 277.0840192243.

The spelling of 21273279 in words is "twenty-one million, two hundred seventy-three thousand, two hundred seventy-nine".