19400611649 has 2 divisors, whose sum is σ = 19400611650. Its totient is φ = 19400611648.

The previous prime is 19400611639. The next prime is 19400611717. The reversal of 19400611649 is 94611600491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16382208049 + 3018403600 = 127993^2 + 54940^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19400611649 is a prime.

It is not a weakly prime, because it can be changed into another prime (19400611639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9700305824 + 9700305825.

It is an arithmetic number, because the mean of its divisors is an integer number (9700305825).

Almost surely, 2^19400611649 is an apocalyptic number.

It is an amenable number.

19400611649 is a deficient number, since it is larger than the sum of its proper divisors (1).

19400611649 is an equidigital number, since it uses as much as digits as its factorization.

19400611649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 41.

The spelling of 19400611649 in words is "nineteen billion, four hundred million, six hundred eleven thousand, six hundred forty-nine".