1263589721939 has 2 divisors, whose sum is σ = 1263589721940. Its totient is φ = 1263589721938.

The previous prime is 1263589721887. The next prime is 1263589721981. The reversal of 1263589721939 is 9391279853621.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1263589721939 - 2²⁰ = 1263588673363 is a prime.

It is not a weakly prime, because it can be changed into another prime (1263589721039) 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, 631794860969 + 631794860970.

It is an arithmetic number, because the mean of its divisors is an integer number (631794860970).

Almost surely, 2^{1263589721939} is an apocalyptic number.

1263589721939 is a deficient number, since it is larger than the sum of its proper divisors (1).

1263589721939 is an equidigital number, since it uses as much as digits as its factorization.

1263589721939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 44089920, while the sum is 65.

The spelling of 1263589721939 in words is "one trillion, two hundred sixty-three billion, five hundred eighty-nine million, seven hundred twenty-one thousand, nine hundred thirty-nine".