6640748145 has 40 divisors (see below), whose sum is σ = 11955416616. Its totient is φ = 3526481664.

The previous prime is 6640748143. The next prime is 6640748201. The reversal of 6640748145 is 5418470466.

6640748145 is a `hidden beast` number, since 66 + 407 + 48 + 145 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 263607696 + 6377140449 = 16236^2 + 79857^2 .

It is not a de Polignac number, because 6640748145 - 2¹ = 6640748143 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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 6640748145.

It is not an unprimeable number, because it can be changed into a prime (6640748143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 59179 + ... + 129551.

Almost surely, 2^6640748145 is an apocalyptic number.

It is an amenable number.

6640748145 is a deficient number, since it is larger than the sum of its proper divisors (5314668471).

6640748145 is a wasteful number, since it uses less digits than its factorization.

6640748145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70623 (or 70614 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The square root of 6640748145 is about 81490.7856447586. The cubic root of 6640748145 is about 1879.6298638492.

The spelling of 6640748145 in words is "six billion, six hundred forty million, seven hundred forty-eight thousand, one hundred forty-five".