6639045261 has 8 divisors (see below), whose sum is σ = 8852437344. Its totient is φ = 4425841680.

The previous prime is 6639045211. The next prime is 6639045263. The reversal of 6639045261 is 1625409366.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6639045261 - 2¹⁸ = 6638783117 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6639045263) 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 7 ways as a sum of consecutive naturals, for example, 108126 + ... + 158016.

It is an arithmetic number, because the mean of its divisors is an integer number (1106554668).

Almost surely, 2^6639045261 is an apocalyptic number.

It is an amenable number.

6639045261 is a deficient number, since it is larger than the sum of its proper divisors (2213392083).

6639045261 is a wasteful number, since it uses less digits than its factorization.

6639045261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94251.

The product of its (nonzero) digits is 233280, while the sum is 42.

The square root of 6639045261 is about 81480.3366524709. The cubic root of 6639045261 is about 1879.4691859064.

The spelling of 6639045261 in words is "six billion, six hundred thirty-nine million, forty-five thousand, two hundred sixty-one".