19805365577939 has 2 divisors, whose sum is σ = 19805365577940. Its totient is φ = 19805365577938.

The previous prime is 19805365577873. The next prime is 19805365577953. The reversal of 19805365577939 is 93977556350891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19805365577939 - 2²⁴ = 19805348800723 is a prime.

It is a super-2 number, since 2×19805365577939² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19805365577939.

It is not a weakly prime, because it can be changed into another prime (19805365577999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9902682788969 + 9902682788970.

It is an arithmetic number, because the mean of its divisors is an integer number (9902682788970).

Almost surely, 2^{19805365577939} is an apocalyptic number.

19805365577939 is a deficient number, since it is larger than the sum of its proper divisors (1).

19805365577939 is an equidigital number, since it uses as much as digits as its factorization.

19805365577939 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1928934000, while the sum is 77.

The spelling of 19805365577939 in words is "nineteen trillion, eight hundred five billion, three hundred sixty-five million, five hundred seventy-seven thousand, nine hundred thirty-nine".