21464279 has 4 divisors (see below), whose sum is σ = 21987840. Its totient is φ = 20940720.

The previous prime is 21464269. The next prime is 21464291. The reversal of 21464279 is 97246412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21464279 - 2²⁴ = 4687063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21464239) 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 3 ways as a sum of consecutive naturals, for example, 261719 + ... + 261800.

It is an arithmetic number, because the mean of its divisors is an integer number (5496960).

Almost surely, 2^21464279 is an apocalyptic number.

21464279 is a deficient number, since it is larger than the sum of its proper divisors (523561).

21464279 is an equidigital number, since it uses as much as digits as its factorization.

21464279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523560.

The product of its digits is 24192, while the sum is 35.

The square root of 21464279 is about 4632.9557520011. The cubic root of 21464279 is about 277.9108067469.

The spelling of 21464279 in words is "twenty-one million, four hundred sixty-four thousand, two hundred seventy-nine".