6645405617 has 4 divisors (see below), whose sum is σ = 6934336320. Its totient is φ = 6356474916.

The previous prime is 6645405607. The next prime is 6645405619. The reversal of 6645405617 is 7165045466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6645405617 - 2⁴ = 6645405601 is a prime.

It is a super-2 number, since 2×6645405617² = 88322831628910301378, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6645405619) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144465317 + ... + 144465362.

It is an arithmetic number, because the mean of its divisors is an integer number (1733584080).

Almost surely, 2^6645405617 is an apocalyptic number.

It is an amenable number.

6645405617 is a deficient number, since it is larger than the sum of its proper divisors (288930703).

6645405617 is a wasteful number, since it uses less digits than its factorization.

6645405617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288930702.

The product of its (nonzero) digits is 604800, while the sum is 44.

The square root of 6645405617 is about 81519.3573146894. The cubic root of 6645405617 is about 1880.0691857178.

The spelling of 6645405617 in words is "six billion, six hundred forty-five million, four hundred five thousand, six hundred seventeen".