85557839 has 2 divisors, whose sum is σ = 85557840. Its totient is φ = 85557838.

The previous prime is 85557809. The next prime is 85557851. The reversal of 85557839 is 93875558.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85557839 - 2²⁰ = 84509263 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85557809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42778919 + 42778920.

It is an arithmetic number, because the mean of its divisors is an integer number (42778920).

Almost surely, 2^85557839 is an apocalyptic number.

85557839 is a deficient number, since it is larger than the sum of its proper divisors (1).

85557839 is an equidigital number, since it uses as much as digits as its factorization.

85557839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512000, while the sum is 50.

The square root of 85557839 is about 9249.7480506228. The cubic root of 85557839 is about 440.6427228859.

The spelling of 85557839 in words is "eighty-five million, five hundred fifty-seven thousand, eight hundred thirty-nine".