123431509987 has 2 divisors, whose sum is σ = 123431509988. Its totient is φ = 123431509986.

The previous prime is 123431509951. The next prime is 123431510051. The reversal of 123431509987 is 789905134321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 123431509987 - 2¹⁵ = 123431477219 is a prime.

It is not a weakly prime, because it can be changed into another prime (123431509907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61715754993 + 61715754994.

It is an arithmetic number, because the mean of its divisors is an integer number (61715754994).

Almost surely, 2^123431509987 is an apocalyptic number.

123431509987 is a deficient number, since it is larger than the sum of its proper divisors (1).

123431509987 is an equidigital number, since it uses as much as digits as its factorization.

123431509987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1632960, while the sum is 52.

The spelling of 123431509987 in words is "one hundred twenty-three billion, four hundred thirty-one million, five hundred nine thousand, nine hundred eighty-seven".