85431581577 has 8 divisors (see below), whose sum is σ = 126565306080. Its totient is φ = 56954387700.

The previous prime is 85431581569. The next prime is 85431581621. The reversal of 85431581577 is 77518513458.

85431581577 is a `hidden beast` number, since 8 + 5 + 4 + 3 + 1 + 581 + 57 + 7 = 666.

It is not a de Polignac number, because 85431581577 - 2³ = 85431581569 is a prime.

It is not an unprimeable number, because it can be changed into a prime (85431581507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1582066299 + ... + 1582066352.

It is an arithmetic number, because the mean of its divisors is an integer number (15820663260).

Almost surely, 2^85431581577 is an apocalyptic number.

It is an amenable number.

85431581577 is a deficient number, since it is larger than the sum of its proper divisors (41133724503).

85431581577 is a wasteful number, since it uses less digits than its factorization.

85431581577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3164132660 (or 3164132654 counting only the distinct ones).

The product of its digits is 4704000, while the sum is 54.

The spelling of 85431581577 in words is "eighty-five billion, four hundred thirty-one million, five hundred eighty-one thousand, five hundred seventy-seven".