1231587139 has 2 divisors, whose sum is σ = 1231587140. Its totient is φ = 1231587138.

The previous prime is 1231587103. The next prime is 1231587157. The reversal of 1231587139 is 9317851321.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1231587139 - 2¹⁵ = 1231554371 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231582139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615793569 + 615793570.

It is an arithmetic number, because the mean of its divisors is an integer number (615793570).

Almost surely, 2^1231587139 is an apocalyptic number.

1231587139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231587139 is an equidigital number, since it uses as much as digits as its factorization.

1231587139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 40.

The square root of 1231587139 is about 35093.9758220695. The cubic root of 1231587139 is about 1071.9019188292.

The spelling of 1231587139 in words is "one billion, two hundred thirty-one million, five hundred eighty-seven thousand, one hundred thirty-nine".