21542316 has 24 divisors (see below), whose sum is σ = 51119040. Its totient is φ = 7058832.

The previous prime is 21542299. The next prime is 21542321. The reversal of 21542316 is 61324512.

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, 14506 + ... + 15921.

It is an arithmetic number, because the mean of its divisors is an integer number (2129960).

Almost surely, 2^21542316 is an apocalyptic number.

It is an amenable number.

21542316 is an abundant number, since it is smaller than the sum of its proper divisors (29576724).

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

21542316 is a wasteful number, since it uses less digits than its factorization.

21542316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30493 (or 30491 counting only the distinct ones).

The product of its digits is 1440, while the sum is 24.

The square root of 21542316 is about 4641.3700563519. The cubic root of 21542316 is about 278.2471965839.

Adding to 21542316 its reverse (61324512), we get a palindrome (82866828).

The spelling of 21542316 in words is "twenty-one million, five hundred forty-two thousand, three hundred sixteen".