123456787654391 has 2 divisors, whose sum is σ = 123456787654392. Its totient is φ = 123456787654390.

The previous prime is 123456787654313. The next prime is 123456787654427. The reversal of 123456787654391 is 193456787654321.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 123456787654391 - 2¹⁸ = 123456787392247 is a prime.

It is a super-3 number, since 3×123456787654391³ (a number of 43 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123456787651391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61728393827195 + 61728393827196.

It is an arithmetic number, because the mean of its divisors is an integer number (61728393827196).

Almost surely, 2^{123456787654391} is an apocalyptic number.

123456787654391 is a deficient number, since it is larger than the sum of its proper divisors (1).

123456787654391 is an equidigital number, since it uses as much as digits as its factorization.

123456787654391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 914457600, while the sum is 71.

The spelling of 123456787654391 in words is "one hundred twenty-three trillion, four hundred fifty-six billion, seven hundred eighty-seven million, six hundred fifty-four thousand, three hundred ninety-one".