21358746 has 12 divisors (see below), whose sum is σ = 46277322. Its totient is φ = 7119576.

The previous prime is 21358739. The next prime is 21358747. The reversal of 21358746 is 64785312.

It can be written as a sum of positive squares in only one way, i.e., 11189025 + 10169721 = 3345^2 + 3189^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21358746.

It is not an unprimeable number, because it can be changed into a prime (21358747) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 593281 + ... + 593316.

Almost surely, 2^21358746 is an apocalyptic number.

21358746 is an abundant number, since it is smaller than the sum of its proper divisors (24918576).

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

21358746 is a wasteful number, since it uses less digits than its factorization.

21358746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1186605 (or 1186602 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 21358746 is about 4621.5523366073. The cubic root of 21358746 is about 277.4545920345.

The spelling of 21358746 in words is "twenty-one million, three hundred fifty-eight thousand, seven hundred forty-six".