19964447 has 2 divisors, whose sum is σ = 19964448. Its totient is φ = 19964446.

The previous prime is 19964429. The next prime is 19964453. The reversal of 19964447 is 74446991.

It is a strong prime.

It is an emirp because it is prime and its reverse (74446991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19964447 - 2²² = 15770143 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 19964398 and 19964407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19964947) 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 as a sum of consecutive naturals, namely, 9982223 + 9982224.

It is an arithmetic number, because the mean of its divisors is an integer number (9982224).

Almost surely, 2^19964447 is an apocalyptic number.

19964447 is a deficient number, since it is larger than the sum of its proper divisors (1).

19964447 is an equidigital number, since it uses as much as digits as its factorization.

19964447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 44.

The square root of 19964447 is about 4468.1592406717. The cubic root of 19964447 is about 271.2808234420.

It can be divided in two parts, 199 and 64447, that added together give a palindrome (64646).

The spelling of 19964447 in words is "nineteen million, nine hundred sixty-four thousand, four hundred forty-seven".