21959441 has 4 divisors (see below), whose sum is σ = 25096512. Its totient is φ = 18822372.

The previous prime is 21959423. The next prime is 21959449. The reversal of 21959441 is 14495912.

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 a de Polignac number, because none of the positive numbers 2^k-21959441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21959449) 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, 1568525 + ... + 1568538.

It is an arithmetic number, because the mean of its divisors is an integer number (6274128).

Almost surely, 2^21959441 is an apocalyptic number.

It is an amenable number.

21959441 is a deficient number, since it is larger than the sum of its proper divisors (3137071).

21959441 is an equidigital number, since it uses as much as digits as its factorization.

21959441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3137070.

The product of its digits is 12960, while the sum is 35.

The square root of 21959441 is about 4686.0901613179. The cubic root of 21959441 is about 280.0316333308.

The spelling of 21959441 in words is "twenty-one million, nine hundred fifty-nine thousand, four hundred forty-one".