85811620 has 48 divisors (see below), whose sum is σ = 190003968. Its totient is φ = 32489600.

The previous prime is 85811599. The next prime is 85811623. The reversal of 85811620 is 2611858.

It is not an unprimeable number, because it can be changed into a prime (85811623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45537 + ... + 47383.

It is an arithmetic number, because the mean of its divisors is an integer number (3958416).

Almost surely, 2^85811620 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 85811620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95001984).

85811620 is an abundant number, since it is smaller than the sum of its proper divisors (104192348).

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

85811620 is a wasteful number, since it uses less digits than its factorization.

85811620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1980 (or 1978 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 85811620 is about 9263.4561584756. The cubic root of 85811620 is about 441.0779698387.

It can be divided in two parts, 8581 and 1620, that added together give a palindrome (10201).

The spelling of 85811620 in words is "eighty-five million, eight hundred eleven thousand, six hundred twenty".