865249056 has 288 divisors, whose sum is σ = 3027024000. Its totient is φ = 233694720.

The previous prime is 865249043. The next prime is 865249057. The reversal of 865249056 is 650942568.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×865249056² = 1497311857817782272, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (865249057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1876666 + ... + 1877126.

It is an arithmetic number, because the mean of its divisors is an integer number (10510500).

Almost surely, 2^865249056 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 865249056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1513512000).

865249056 is an abundant number, since it is smaller than the sum of its proper divisors (2161774944).

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

865249056 is a wasteful number, since it uses less digits than its factorization.

865249056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 517 (or 492 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The square root of 865249056 is about 29415.1161139983. The cubic root of 865249056 is about 952.8993807431.

The spelling of 865249056 in words is "eight hundred sixty-five million, two hundred forty-nine thousand, fifty-six".