865275840 has 504 divisors, whose sum is σ = 3541434624. Its totient is φ = 192614400.

The previous prime is 865275833. The next prime is 865275841. The reversal of 865275840 is 48572568.

865275840 is a `hidden beast` number, since 8 + 65 + 2 + 7 + 584 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (865275841) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 4530145 + ... + 4530335.

It is an arithmetic number, because the mean of its divisors is an integer number (7026656).

Almost surely, 2^865275840 is an apocalyptic number.

865275840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 865275840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1770717312).

865275840 is an abundant number, since it is smaller than the sum of its proper divisors (2676158784).

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

865275840 is a wasteful number, since it uses less digits than its factorization.

865275840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The square root of 865275840 is about 29415.5713865973. The cubic root of 865275840 is about 952.9092130542.

The spelling of 865275840 in words is "eight hundred sixty-five million, two hundred seventy-five thousand, eight hundred forty".