85669640 has 96 divisors (see below), whose sum is σ = 226848600. Its totient is φ = 29030400.

The previous prime is 85669627. The next prime is 85669643. The reversal of 85669640 is 4696658.

It can be written as a sum of positive squares in 4 ways, for example, as 85636516 + 33124 = 9254^2 + 182^2 .

It is a junction number, because it is equal to n+sod(n) for n = 85669591 and 85669600.

It is not an unprimeable number, because it can be changed into a prime (85669643) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 213440 + ... + 213840.

Almost surely, 2^85669640 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 85669640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113424300).

85669640 is an abundant number, since it is smaller than the sum of its proper divisors (141178960).

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

85669640 is a wasteful number, since it uses less digits than its factorization.

85669640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535 (or 524 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 44.

The square root of 85669640 is about 9255.7895395261. The cubic root of 85669640 is about 440.8345730418.

The spelling of 85669640 in words is "eighty-five million, six hundred sixty-nine thousand, six hundred forty".