21724092 has 48 divisors (see below), whose sum is σ = 60658080. Its totient is φ = 6683904.

The previous prime is 21724091. The next prime is 21724097. The reversal of 21724092 is 29042712.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21724091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6333 + ... + 9140.

It is an arithmetic number, because the mean of its divisors is an integer number (1263710).

Almost surely, 2^21724092 is an apocalyptic number.

It is an amenable number.

21724092 is an abundant number, since it is smaller than the sum of its proper divisors (38933988).

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

21724092 is a wasteful number, since it uses less digits than its factorization.

21724092 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15499 (or 15491 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21724092 is about 4660.9110697373. The cubic root of 21724092 is about 279.0276305159.

The spelling of 21724092 in words is "twenty-one million, seven hundred twenty-four thousand, ninety-two".