19440509947 has 2 divisors, whose sum is σ = 19440509948. Its totient is φ = 19440509946.

The previous prime is 19440509941. The next prime is 19440510029. The reversal of 19440509947 is 74990504491.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19440509947 - 2¹⁹ = 19439985659 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19440509894 and 19440509903.

It is not a weakly prime, because it can be changed into another prime (19440509941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9720254973 + 9720254974.

It is an arithmetic number, because the mean of its divisors is an integer number (9720254974).

Almost surely, 2^19440509947 is an apocalyptic number.

19440509947 is a deficient number, since it is larger than the sum of its proper divisors (1).

19440509947 is an equidigital number, since it uses as much as digits as its factorization.

19440509947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1632960, while the sum is 52.

The spelling of 19440509947 in words is "nineteen billion, four hundred forty million, five hundred nine thousand, nine hundred forty-seven".