21468391 has 8 divisors (see below), whose sum is σ = 24566144. Its totient is φ = 18378360.

The previous prime is 21468383. The next prime is 21468397. The reversal of 21468391 is 19386412.

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

It is not a de Polignac number, because 21468391 - 2³ = 21468383 is a prime.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21468397) 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, 6496 + ... + 9226.

It is an arithmetic number, because the mean of its divisors is an integer number (3070768).

Almost surely, 2^21468391 is an apocalyptic number.

21468391 is a deficient number, since it is larger than the sum of its proper divisors (3097753).

21468391 is a wasteful number, since it uses less digits than its factorization.

21468391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3861.

The product of its digits is 10368, while the sum is 34.

The square root of 21468391 is about 4633.3995079207. The cubic root of 21468391 is about 277.9285524516.

The spelling of 21468391 in words is "twenty-one million, four hundred sixty-eight thousand, three hundred ninety-one".