6635865645 has 12 divisors (see below), whose sum is σ = 11502167196. Its totient is φ = 3539128320.

The previous prime is 6635865623. The next prime is 6635865659. The reversal of 6635865645 is 5465685366.

6635865645 is a `hidden beast` number, since 6 + 6 + 3 + 586 + 56 + 4 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3317414409 + 3318451236 = 57597^2 + 57606^2 .

It is not a de Polignac number, because 6635865645 - 2⁶ = 6635865581 is a prime.

It is a super-3 number, since 3×6635865645³ (a number of 30 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6635865591 and 6635865600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 73731796 + ... + 73731885.

It is an arithmetic number, because the mean of its divisors is an integer number (958513933).

Almost surely, 2^6635865645 is an apocalyptic number.

It is an amenable number.

6635865645 is a deficient number, since it is larger than the sum of its proper divisors (4866301551).

6635865645 is a wasteful number, since it uses less digits than its factorization.

6635865645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147463692 (or 147463689 counting only the distinct ones).

The product of its digits is 15552000, while the sum is 54.

The square root of 6635865645 is about 81460.8227616196. The cubic root of 6635865645 is about 1879.1690953394.

The spelling of 6635865645 in words is "six billion, six hundred thirty-five million, eight hundred sixty-five thousand, six hundred forty-five".