1139987531 has 2 divisors, whose sum is σ = 1139987532. Its totient is φ = 1139987530.

The previous prime is 1139987507. The next prime is 1139987543. The reversal of 1139987531 is 1357899311.

It is a strong prime.

It is an emirp because it is prime and its reverse (1357899311) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1139987531 is a prime.

It is a super-2 number, since 2×1139987531² = 2599143141670951922, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1139987551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 569993765 + 569993766.

It is an arithmetic number, because the mean of its divisors is an integer number (569993766).

Almost surely, 2^1139987531 is an apocalyptic number.

1139987531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1139987531 is an equidigital number, since it uses as much as digits as its factorization.

1139987531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 47.

The square root of 1139987531 is about 33763.7013818094. The cubic root of 1139987531 is about 1044.6401181344.

The spelling of 1139987531 in words is "one billion, one hundred thirty-nine million, nine hundred eighty-seven thousand, five hundred thirty-one".