85659840 has 252 divisors, whose sum is σ = 343302336. Its totient is φ = 19547136.

The previous prime is 85659839. The next prime is 85659853. The reversal of 85659840 is 4895658.

85659840 is a `hidden beast` number, since 8 + 56 + 598 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (252).

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 35 ways as a sum of consecutive naturals, for example, 140817 + ... + 141423.

Almost surely, 2^85659840 is an apocalyptic number.

85659840 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 85659840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171651168).

85659840 is an abundant number, since it is smaller than the sum of its proper divisors (257642496).

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

85659840 is a wasteful number, since it uses less digits than its factorization.

85659840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 85659840 is about 9255.2601260040. The cubic root of 85659840 is about 440.8177629499.

The spelling of 85659840 in words is "eighty-five million, six hundred fifty-nine thousand, eight hundred forty".