865571940 has 96 divisors (see below), whose sum is σ = 2755589760. Its totient is φ = 225445248.

The previous prime is 865571921. The next prime is 865571947. The reversal of 865571940 is 49175568.

865571940 is a `hidden beast` number, since 8 + 6 + 557 + 1 + 94 + 0 = 666.

865571940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not an unprimeable number, because it can be changed into a prime (865571947) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4582 + ... + 41858.

It is an arithmetic number, because the mean of its divisors is an integer number (28704060).

Almost surely, 2^865571940 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 865571940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1377794880).

865571940 is an abundant number, since it is smaller than the sum of its proper divisors (1890017820).

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

865571940 is a wasteful number, since it uses less digits than its factorization.

865571940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37338 (or 37330 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The square root of 865571940 is about 29420.6040046767. The cubic root of 865571940 is about 953.0178967926.

The spelling of 865571940 in words is "eight hundred sixty-five million, five hundred seventy-one thousand, nine hundred forty".