1231789717393 has 2 divisors, whose sum is σ = 1231789717394. Its totient is φ = 1231789717392.

The previous prime is 1231789717357. The next prime is 1231789717423. The reversal of 1231789717393 is 3937179871321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1230928118784 + 861598609 = 1109472^2 + 29353^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1231789717393 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231789717493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615894858696 + 615894858697.

It is an arithmetic number, because the mean of its divisors is an integer number (615894858697).

Almost surely, 2^{1231789717393} is an apocalyptic number.

It is an amenable number.

1231789717393 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231789717393 is an equidigital number, since it uses as much as digits as its factorization.

1231789717393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12002256, while the sum is 61.

The spelling of 1231789717393 in words is "one trillion, two hundred thirty-one billion, seven hundred eighty-nine million, seven hundred seventeen thousand, three hundred ninety-three".