2185767864 has 96 divisors (see below), whose sum is σ = 6776939520. Its totient is φ = 623446848.

The previous prime is 2185767827. The next prime is 2185767869. The reversal of 2185767864 is 4687675812.

2185767864 is a `hidden beast` number, since 2 + 1 + 8 + 576 + 7 + 8 + 64 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 2185767864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2185767869) 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, 322737 + ... + 329439.

It is an arithmetic number, because the mean of its divisors is an integer number (70593120).

Almost surely, 2^2185767864 is an apocalyptic number.

2185767864 is a gapful number since it is divisible by the number (24) 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 2185767864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3388469760).

2185767864 is an abundant number, since it is smaller than the sum of its proper divisors (4591171656).

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

2185767864 is a wasteful number, since it uses less digits than its factorization.

2185767864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7369 (or 7362 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 54.

The square root of 2185767864 is about 46752.1963548238. The cubic root of 2185767864 is about 1297.7808023788.

The spelling of 2185767864 in words is "two billion, one hundred eighty-five million, seven hundred sixty-seven thousand, eight hundred sixty-four".