85631940 has 72 divisors (see below), whose sum is σ = 260828568. Its totient is φ = 22740480.

The previous prime is 85631851. The next prime is 85631957. The reversal of 85631940 is 4913658.

85631940 is a `hidden beast` number, since 8 + 563 + 1 + 94 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 10150596 + 75481344 = 3186^2 + 8688^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 85631895 and 85631904.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 49734 + ... + 51426.

It is an arithmetic number, because the mean of its divisors is an integer number (3622619).

Almost surely, 2^85631940 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 85631940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130414284).

85631940 is an abundant number, since it is smaller than the sum of its proper divisors (175196628).

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

85631940 is a wasteful number, since it uses less digits than its factorization.

85631940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1989 (or 1984 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 85631940 is about 9253.7527522622. The cubic root of 85631940 is about 440.7698986255.

It can be divided in two parts, 85 and 631940, that added together give a square (632025 = 795²).

The spelling of 85631940 in words is "eighty-five million, six hundred thirty-one thousand, nine hundred forty".