6645117388 has 24 divisors (see below), whose sum is σ = 14312561312. Its totient is φ = 2628837504.

The previous prime is 6645117383. The next prime is 6645117421. The reversal of 6645117388 is 8837115466.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (6645117383) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9127545 + ... + 9128272.

Almost surely, 2^6645117388 is an apocalyptic number.

It is an amenable number.

6645117388 is an abundant number, since it is smaller than the sum of its proper divisors (7667443924).

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

6645117388 is a wasteful number, since it uses less digits than its factorization.

6645117388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18255841 (or 18255839 counting only the distinct ones).

The product of its digits is 967680, while the sum is 49.

The square root of 6645117388 is about 81517.5894393351. The cubic root of 6645117388 is about 1880.0420041166.

The spelling of 6645117388 in words is "six billion, six hundred forty-five million, one hundred seventeen thousand, three hundred eighty-eight".