21461339 has 4 divisors (see below), whose sum is σ = 21470856. Its totient is φ = 21451824.

The previous prime is 21461329. The next prime is 21461357. The reversal of 21461339 is 93316412.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21461339 - 2²⁴ = 4684123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21461329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 752 + ... + 6594.

It is an arithmetic number, because the mean of its divisors is an integer number (5367714).

Almost surely, 2^21461339 is an apocalyptic number.

21461339 is a deficient number, since it is larger than the sum of its proper divisors (9517).

21461339 is an equidigital number, since it uses as much as digits as its factorization.

21461339 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9516.

The product of its digits is 3888, while the sum is 29.

The square root of 21461339 is about 4632.6384490914. The cubic root of 21461339 is about 277.8981175237.

The spelling of 21461339 in words is "twenty-one million, four hundred sixty-one thousand, three hundred thirty-nine".