21849573 has 16 divisors (see below), whose sum is σ = 31682880. Its totient is φ = 13337856.

The previous prime is 21849559. The next prime is 21849587. The reversal of 21849573 is 37594812.

It is an interprime number because it is at equal distance from previous prime (21849559) and next prime (21849587).

It is a de Polignac number, because none of the positive numbers 2^k-21849573 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21849523) 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, 3903 + ... + 7676.

It is an arithmetic number, because the mean of its divisors is an integer number (1980180).

Almost surely, 2^21849573 is an apocalyptic number.

It is an amenable number.

21849573 is a deficient number, since it is larger than the sum of its proper divisors (9833307).

21849573 is a wasteful number, since it uses less digits than its factorization.

21849573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11636.

The product of its digits is 60480, while the sum is 39.

The square root of 21849573 is about 4674.3526824578. The cubic root of 21849573 is about 279.5638319695.

It can be divided in two parts, 21849 and 573, that added together give a palindrome (22422).

The spelling of 21849573 in words is "twenty-one million, eight hundred forty-nine thousand, five hundred seventy-three".