2165775612 has 288 divisors, whose sum is σ = 7037108736. Its totient is φ = 504092160.

The previous prime is 2165775589. The next prime is 2165775613.

It is a happy number.

2165775612 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2165775613) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4888663 + ... + 4889105.

Almost surely, 2^2165775612 is an apocalyptic number.

2165775612 is a gapful number since it is divisible by the number (22) 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 2165775612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3518554368).

2165775612 is an abundant number, since it is smaller than the sum of its proper divisors (4871333124).

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

2165775612 is a wasteful number, since it uses less digits than its factorization.

2165775612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529 (or 516 counting only the distinct ones).

The product of its digits is 176400, while the sum is 42.

The square root of 2165775612 is about 46537.8943657747. The cubic root of 2165775612 is about 1293.8119348258.

It can be divided in two parts, 2165 and 775612, that added together give a palindrome (777777).

The spelling of 2165775612 in words is "two billion, one hundred sixty-five million, seven hundred seventy-five thousand, six hundred twelve".