6639340545 has 48 divisors (see below), whose sum is σ = 11796138432. Its totient is φ = 3453436800.

The previous prime is 6639340541. The next prime is 6639340549. The reversal of 6639340545 is 5450439366.

6639340545 is a `hidden beast` number, since 6 + 63 + 9 + 3 + 40 + 545 = 666.

It is an interprime number because it is at equal distance from previous prime (6639340541) and next prime (6639340549).

It is not a de Polignac number, because 6639340545 - 2² = 6639340541 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 6639340545.

It is not an unprimeable number, because it can be changed into a prime (6639340541) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 293614 + ... + 315416.

It is an arithmetic number, because the mean of its divisors is an integer number (245752884).

Almost surely, 2^6639340545 is an apocalyptic number.

It is an amenable number.

6639340545 is a deficient number, since it is larger than the sum of its proper divisors (5156797887).

6639340545 is a wasteful number, since it uses less digits than its factorization.

6639340545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21982 (or 21979 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 45.

The square root of 6639340545 is about 81482.1486277823. The cubic root of 6639340545 is about 1879.4970498000.

The spelling of 6639340545 in words is "six billion, six hundred thirty-nine million, three hundred forty thousand, five hundred forty-five".