65665000 has 80 divisors (see below), whose sum is σ = 160823520. Its totient is φ = 25080000.

The previous prime is 65664997. The next prime is 65665009. The reversal of 65665000 is 56656.

It is a self number, because there is not a number n which added to its sum of digits gives 65665000.

It is not an unprimeable number, because it can be changed into a prime (65665009) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 114715 + ... + 115285.

It is an arithmetic number, because the mean of its divisors is an integer number (2010294).

Almost surely, 2^65665000 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 65665000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80411760).

65665000 is an abundant number, since it is smaller than the sum of its proper divisors (95158520).

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

65665000 is a wasteful number, since it uses less digits than its factorization.

65665000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 620 (or 601 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 65665000 is about 8103.3943505176. The cubic root of 65665000 is about 403.4390967924.

It can be divided in two parts, 656 and 65000, that added together give a palindrome (65656).

The spelling of 65665000 in words is "sixty-five million, six hundred sixty-five thousand".