21944353 has 4 divisors (see below), whose sum is σ = 21966868. Its totient is φ = 21921840.

The previous prime is 21944333. The next prime is 21944357. The reversal of 21944353 is 35344912.

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 6671889 + 15272464 = 2583^2 + 3908^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21944353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21944357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9726 + ... + 11767.

It is an arithmetic number, because the mean of its divisors is an integer number (5491717).

Almost surely, 2^21944353 is an apocalyptic number.

It is an amenable number.

21944353 is a deficient number, since it is larger than the sum of its proper divisors (22515).

21944353 is a wasteful number, since it uses less digits than its factorization.

21944353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22514.

The product of its digits is 12960, while the sum is 31.

The square root of 21944353 is about 4684.4800138329. The cubic root of 21944353 is about 279.9674834689.

The spelling of 21944353 in words is "twenty-one million, nine hundred forty-four thousand, three hundred fifty-three".