85131139 has 2 divisors, whose sum is σ = 85131140. Its totient is φ = 85131138.

The previous prime is 85131133. The next prime is 85131161. The reversal of 85131139 is 93113158.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 85131139 - 2⁹ = 85130627 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 85131139.

It is not a weakly prime, because it can be changed into another prime (85131133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42565569 + 42565570.

It is an arithmetic number, because the mean of its divisors is an integer number (42565570).

Almost surely, 2^85131139 is an apocalyptic number.

85131139 is a deficient number, since it is larger than the sum of its proper divisors (1).

85131139 is an equidigital number, since it uses as much as digits as its factorization.

85131139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3240, while the sum is 31.

The square root of 85131139 is about 9226.6537271104. The cubic root of 85131139 is about 439.9089670488.

The spelling of 85131139 in words is "eighty-five million, one hundred thirty-one thousand, one hundred thirty-nine".