21444859 has 2 divisors, whose sum is σ = 21444860. Its totient is φ = 21444858.

The previous prime is 21444853. The next prime is 21444877. The reversal of 21444859 is 95844412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21444859 - 2⁹ = 21444347 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21444853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722429 + 10722430.

It is an arithmetic number, because the mean of its divisors is an integer number (10722430).

Almost surely, 2^21444859 is an apocalyptic number.

21444859 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444859 is an equidigital number, since it uses as much as digits as its factorization.

21444859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46080, while the sum is 37.

The square root of 21444859 is about 4630.8594234764. The cubic root of 21444859 is about 277.8269673541.

The spelling of 21444859 in words is "twenty-one million, four hundred forty-four thousand, eight hundred fifty-nine".