19791262609 has 2 divisors, whose sum is σ = 19791262610. Its totient is φ = 19791262608.

The previous prime is 19791262591. The next prime is 19791262639. The reversal of 19791262609 is 90626219791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16155172609 + 3636090000 = 127103^2 + 60300^2 .

It is a cyclic number.

It is not a de Polignac number, because 19791262609 - 2⁵ = 19791262577 is a prime.

It is not a weakly prime, because it can be changed into another prime (19791262639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9895631304 + 9895631305.

It is an arithmetic number, because the mean of its divisors is an integer number (9895631305).

Almost surely, 2^19791262609 is an apocalyptic number.

It is an amenable number.

19791262609 is a deficient number, since it is larger than the sum of its proper divisors (1).

19791262609 is an equidigital number, since it uses as much as digits as its factorization.

19791262609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 734832, while the sum is 52.

The spelling of 19791262609 in words is "nineteen billion, seven hundred ninety-one million, two hundred sixty-two thousand, six hundred nine".