21444419 has 2 divisors, whose sum is σ = 21444420. Its totient is φ = 21444418.

The previous prime is 21444413. The next prime is 21444431. The reversal of 21444419 is 91444412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21444419 - 2¹⁶ = 21378883 is a prime.

It is a super-2 number, since 2×21444419² = 919726212495122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21444391 and 21444400.

It is not a weakly prime, because it can be changed into another prime (21444413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722209 + 10722210.

It is an arithmetic number, because the mean of its divisors is an integer number (10722210).

Almost surely, 2^21444419 is an apocalyptic number.

21444419 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444419 is an equidigital number, since it uses as much as digits as its factorization.

21444419 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4608, while the sum is 29.

The square root of 21444419 is about 4630.8119158523. The cubic root of 21444419 is about 277.8250672141.

The spelling of 21444419 in words is "twenty-one million, four hundred forty-four thousand, four hundred nineteen".