6640602891 has 16 divisors (see below), whose sum is σ = 9537247776. Its totient is φ = 4085657856.

The previous prime is 6640602851. The next prime is 6640602971. The reversal of 6640602891 is 1982060466.

6640602891 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6640602891 - 2⁷ = 6640602763 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6640602841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 202071 + ... + 232623.

It is an arithmetic number, because the mean of its divisors is an integer number (596077986).

Almost surely, 2^6640602891 is an apocalyptic number.

6640602891 is a deficient number, since it is larger than the sum of its proper divisors (2896644885).

6640602891 is a wasteful number, since it uses less digits than its factorization.

6640602891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36142.

The product of its (nonzero) digits is 124416, while the sum is 42.

The square root of 6640602891 is about 81489.8944102887. The cubic root of 6640602891 is about 1879.6161592816.

The spelling of 6640602891 in words is "six billion, six hundred forty million, six hundred two thousand, eight hundred ninety-one".