21849229 has 4 divisors (see below), whose sum is σ = 22065660. Its totient is φ = 21632800.

The previous prime is 21849227. The next prime is 21849257. The reversal of 21849229 is 92294812.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18966025 + 2883204 = 4355^2 + 1698^2 .

It is a cyclic number.

It is not a de Polignac number, because 21849229 - 2¹ = 21849227 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 (21849227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108064 + ... + 108265.

It is an arithmetic number, because the mean of its divisors is an integer number (5516415).

Almost surely, 2^21849229 is an apocalyptic number.

It is an amenable number.

21849229 is a deficient number, since it is larger than the sum of its proper divisors (216431).

21849229 is a wasteful number, since it uses less digits than its factorization.

21849229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216430.

The product of its digits is 20736, while the sum is 37.

The square root of 21849229 is about 4674.3158857741. The cubic root of 21849229 is about 279.5623648095.

The spelling of 21849229 in words is "twenty-one million, eight hundred forty-nine thousand, two hundred twenty-nine".