1263911795989 has 2 divisors, whose sum is σ = 1263911795990. Its totient is φ = 1263911795988.

The previous prime is 1263911795959. The next prime is 1263911796013. The reversal of 1263911795989 is 9895971193621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1254276803025 + 9634992964 = 1119945^2 + 98158^2 .

It is a cyclic number.

It is not a de Polignac number, because 1263911795989 - 2²³ = 1263903407381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1263911795959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 631955897994 + 631955897995.

It is an arithmetic number, because the mean of its divisors is an integer number (631955897995).

Almost surely, 2^{1263911795989} is an apocalyptic number.

It is an amenable number.

1263911795989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1263911795989 is an equidigital number, since it uses as much as digits as its factorization.

1263911795989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 66134880, while the sum is 70.

The spelling of 1263911795989 in words is "one trillion, two hundred sixty-three billion, nine hundred eleven million, seven hundred ninety-five thousand, nine hundred eighty-nine".