85871557 has 2 divisors, whose sum is σ = 85871558. Its totient is φ = 85871556.

The previous prime is 85871549. The next prime is 85871587. The reversal of 85871557 is 75517858.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 82609921 + 3261636 = 9089^2 + 1806^2 .

It is a cyclic number.

It is not a de Polignac number, because 85871557 - 2³ = 85871549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85871537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42935778 + 42935779.

It is an arithmetic number, because the mean of its divisors is an integer number (42935779).

Almost surely, 2^85871557 is an apocalyptic number.

It is an amenable number.

85871557 is a deficient number, since it is larger than the sum of its proper divisors (1).

85871557 is an equidigital number, since it uses as much as digits as its factorization.

85871557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 392000, while the sum is 46.

The square root of 85871557 is about 9266.6907253884. The cubic root of 85871557 is about 441.1806394520.

The spelling of 85871557 in words is "eighty-five million, eight hundred seventy-one thousand, five hundred fifty-seven".