21431468 has 12 divisors (see below), whose sum is σ = 39479160. Its totient is φ = 10151712.

The previous prime is 21431401. The next prime is 21431489. The reversal of 21431468 is 86413412.

It is a self number, because there is not a number n which added to its sum of digits gives 21431468.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140921 + ... + 141072.

It is an arithmetic number, because the mean of its divisors is an integer number (3289930).

Almost surely, 2^21431468 is an apocalyptic number.

It is an amenable number.

21431468 is a deficient number, since it is larger than the sum of its proper divisors (18047692).

21431468 is a wasteful number, since it uses less digits than its factorization.

21431468 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282016 (or 282014 counting only the distinct ones).

The product of its digits is 4608, while the sum is 29.

The square root of 21431468 is about 4629.4133537631. The cubic root of 21431468 is about 277.7691266758.

The spelling of 21431468 in words is "twenty-one million, four hundred thirty-one thousand, four hundred sixty-eight".