21542893 has 8 divisors (see below), whose sum is σ = 22863168. Its totient is φ = 20228544.

The previous prime is 21542879. The next prime is 21542897. The reversal of 21542893 is 39824512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21542893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21542897) 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, 7680 + ... + 10102.

It is an arithmetic number, because the mean of its divisors is an integer number (2857896).

Almost surely, 2^21542893 is an apocalyptic number.

It is an amenable number.

21542893 is a deficient number, since it is larger than the sum of its proper divisors (1320275).

21542893 is a wasteful number, since it uses less digits than its factorization.

21542893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2963.

The product of its digits is 17280, while the sum is 34.

The square root of 21542893 is about 4641.4322143063. The cubic root of 21542893 is about 278.2496807983.

The spelling of 21542893 in words is "twenty-one million, five hundred forty-two thousand, eight hundred ninety-three".