86139509 has 2 divisors, whose sum is σ = 86139510. Its totient is φ = 86139508.

The previous prime is 86139491. The next prime is 86139517. The reversal of 86139509 is 90593168.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65691025 + 20448484 = 8105^2 + 4522^2 .

It is a cyclic number.

It is not a de Polignac number, because 86139509 - 2¹⁶ = 86073973 is a prime.

It is a super-2 number, since 2×86139509² = 14840030021522162, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86139569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43069754 + 43069755.

It is an arithmetic number, because the mean of its divisors is an integer number (43069755).

Almost surely, 2^86139509 is an apocalyptic number.

It is an amenable number.

86139509 is a deficient number, since it is larger than the sum of its proper divisors (1).

86139509 is an equidigital number, since it uses as much as digits as its factorization.

86139509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 86139509 is about 9281.1372686756. The cubic root of 86139509 is about 441.6390469181.

The spelling of 86139509 in words is "eighty-six million, one hundred thirty-nine thousand, five hundred nine".