85215431808 has 640 divisors, whose sum is σ = 283648780800. Its totient is φ = 25231564800.

The previous prime is 85215431783. The next prime is 85215431809. The reversal of 85215431808 is 80813451258.

85215431808 is a `hidden beast` number, since 8 + 5 + 21 + 543 + 1 + 80 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (85215431809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 564340533 + ... + 564340683.

It is an arithmetic number, because the mean of its divisors is an integer number (443201220).

Almost surely, 2^85215431808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 85215431808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141824390400).

85215431808 is an abundant number, since it is smaller than the sum of its proper divisors (198433348992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

85215431808 is a wasteful number, since it uses less digits than its factorization.

85215431808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322 (or 301 counting only the distinct ones).

The product of its (nonzero) digits is 307200, while the sum is 45.

The spelling of 85215431808 in words is "eighty-five billion, two hundred fifteen million, four hundred thirty-one thousand, eight hundred eight".