21268842 has 48 divisors (see below), whose sum is σ = 50211072. Its totient is φ = 5987520.

The previous prime is 21268837. The next prime is 21268867. The reversal of 21268842 is 24886212.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20967 + ... + 21957.

It is an arithmetic number, because the mean of its divisors is an integer number (1046064).

Almost surely, 2^21268842 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21268842, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25105536).

21268842 is an abundant number, since it is smaller than the sum of its proper divisors (28942230).

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

21268842 is a wasteful number, since it uses less digits than its factorization.

21268842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1083 (or 1076 counting only the distinct ones).

The product of its digits is 12288, while the sum is 33.

The square root of 21268842 is about 4611.8154776617. The cubic root of 21268842 is about 277.0647539404.

The spelling of 21268842 in words is "twenty-one million, two hundred sixty-eight thousand, eight hundred forty-two".