865309140 has 72 divisors (see below), whose sum is σ = 2631599880. Its totient is φ = 230148864.

The previous prime is 865309099. The next prime is 865309147. The reversal of 865309140 is 41903568.

865309140 is a `hidden beast` number, since 86 + 530 + 9 + 1 + 40 = 666.

865309140 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 422795844 + 442513296 = 20562^2 + 21036^2 .

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 = 865309095 and 865309104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (865309147) 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, 65406 + ... + 77514.

Almost surely, 2^865309140 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 865309140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1315799940).

865309140 is an abundant number, since it is smaller than the sum of its proper divisors (1766290740).

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

865309140 is a wasteful number, since it uses less digits than its factorization.

865309140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12521 (or 12516 counting only the distinct ones).

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

The square root of 865309140 is about 29416.1374078923. The cubic root of 865309140 is about 952.9214370827.

The spelling of 865309140 in words is "eight hundred sixty-five million, three hundred nine thousand, one hundred forty".