21830449 has 4 divisors (see below), whose sum is σ = 22979440. Its totient is φ = 20681460.

The previous prime is 21830387. The next prime is 21830453. The reversal of 21830449 is 94403812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21830449 - 2²¹ = 19733297 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21830449.

It is not an unprimeable number, because it can be changed into a prime (21831449) 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, 574467 + ... + 574504.

It is an arithmetic number, because the mean of its divisors is an integer number (5744860).

Almost surely, 2^21830449 is an apocalyptic number.

It is an amenable number.

21830449 is a deficient number, since it is larger than the sum of its proper divisors (1148991).

21830449 is a wasteful number, since it uses less digits than its factorization.

21830449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1148990.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 21830449 is about 4672.3066038093. The cubic root of 21830449 is about 279.4822447260.

The spelling of 21830449 in words is "twenty-one million, eight hundred thirty thousand, four hundred forty-nine".