21342912 has 56 divisors (see below), whose sum is σ = 57150000. Its totient is φ = 7028736.

The previous prime is 21342907. The next prime is 21342943. The reversal of 21342912 is 21924312.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16464 + ... + 17712.

Almost surely, 2^21342912 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21342912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28575000).

21342912 is an abundant number, since it is smaller than the sum of its proper divisors (35807088).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21342912 is a wasteful number, since it uses less digits than its factorization.

21342912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1353 (or 1343 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The square root of 21342912 is about 4619.8389582322. The cubic root of 21342912 is about 277.3860127575.

The spelling of 21342912 in words is "twenty-one million, three hundred forty-two thousand, nine hundred twelve".