1261294423639 has 2 divisors, whose sum is σ = 1261294423640. Its totient is φ = 1261294423638.

The previous prime is 1261294423583. The next prime is 1261294423643. The reversal of 1261294423639 is 9363244921621.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1261294423639 - 2⁷ = 1261294423511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1261294427639) 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, 630647211819 + 630647211820.

It is an arithmetic number, because the mean of its divisors is an integer number (630647211820).

Almost surely, 2^{1261294423639} is an apocalyptic number.

1261294423639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261294423639 is an equidigital number, since it uses as much as digits as its factorization.

1261294423639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3359232, while the sum is 52.

The spelling of 1261294423639 in words is "one trillion, two hundred sixty-one billion, two hundred ninety-four million, four hundred twenty-three thousand, six hundred thirty-nine".