19444661 has 2 divisors, whose sum is σ = 19444662. Its totient is φ = 19444660.

The previous prime is 19444639. The next prime is 19444679. The reversal of 19444661 is 16644491.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11771761 + 7672900 = 3431^2 + 2770^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19444661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19444261) 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, 9722330 + 9722331.

It is an arithmetic number, because the mean of its divisors is an integer number (9722331).

Almost surely, 2^19444661 is an apocalyptic number.

It is an amenable number.

19444661 is a deficient number, since it is larger than the sum of its proper divisors (1).

19444661 is an equidigital number, since it uses as much as digits as its factorization.

19444661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 35.

The square root of 19444661 is about 4409.6100734645. The cubic root of 19444661 is about 268.9057726107.

The spelling of 19444661 in words is "nineteen million, four hundred forty-four thousand, six hundred sixty-one".