21542874 has 16 divisors (see below), whose sum is σ = 43248000. Its totient is φ = 7153920.

The previous prime is 21542849. The next prime is 21542879. The reversal of 21542874 is 47824512.

It is not an unprimeable number, because it can be changed into a prime (21542879) 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, 4999 + ... + 8250.

It is an arithmetic number, because the mean of its divisors is an integer number (2703000).

Almost surely, 2^21542874 is an apocalyptic number.

21542874 is an abundant number, since it is smaller than the sum of its proper divisors (21705126).

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

21542874 is a wasteful number, since it uses less digits than its factorization.

21542874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13525.

The product of its digits is 17920, while the sum is 33.

The square root of 21542874 is about 4641.4301675238. The cubic root of 21542874 is about 278.2495989965.

The spelling of 21542874 in words is "twenty-one million, five hundred forty-two thousand, eight hundred seventy-four".