85639680 has 400 divisors, whose sum is σ = 356495040. Its totient is φ = 19243008.

The previous prime is 85639667. The next prime is 85639691. The reversal of 85639680 is 8693658.

85639680 is a `hidden beast` number, since 8 + 5 + 639 + 6 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1451491 + ... + 1451549.

Almost surely, 2^85639680 is an apocalyptic number.

85639680 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 85639680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178247520).

85639680 is an abundant number, since it is smaller than the sum of its proper divisors (270855360).

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

85639680 is an equidigital number, since it uses as much as digits as its factorization.

85639680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 85639680 is about 9254.1709515223. The cubic root of 85639680 is about 440.7831781574.

The spelling of 85639680 in words is "eighty-five million, six hundred thirty-nine thousand, six hundred eighty".