865535616 has 192 divisors, whose sum is σ = 2740046400. Its totient is φ = 260075520.

The previous prime is 865535581. The next prime is 865535617. The reversal of 865535616 is 616535568.

865535616 is a `hidden beast` number, since 86 + 5 + 5 + 3 + 561 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is not an unprimeable number, because it can be changed into a prime (865535617) 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, 2116020 + ... + 2116428.

It is an arithmetic number, because the mean of its divisors is an integer number (14271075).

Almost surely, 2^865535616 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 865535616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1370023200).

865535616 is an abundant number, since it is smaller than the sum of its proper divisors (1874510784).

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

865535616 is a wasteful number, since it uses less digits than its factorization.

865535616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 607 (or 592 counting only the distinct ones).

The product of its digits is 648000, while the sum is 45.

The square root of 865535616 is about 29419.9866757278. The cubic root of 865535616 is about 953.0045653737.

The spelling of 865535616 in words is "eight hundred sixty-five million, five hundred thirty-five thousand, six hundred sixteen".