6479872781 has 8 divisors (see below), whose sum is σ = 6704602680. Its totient is φ = 6255228672.

The previous prime is 6479872769. The next prime is 6479872807. The reversal of 6479872781 is 1872789746.

It can be written as a sum of positive squares in 4 ways, for example, as 890067556 + 5589805225 = 29834^2 + 74765^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 6479872781 - 2³⁰ = 5406130957 is a prime.

It is a super-2 number, since 2×6479872781² = 83977502515889347922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6479872781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6479872741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 157721 + ... + 194513.

It is an arithmetic number, because the mean of its divisors is an integer number (838075335).

Almost surely, 2^6479872781 is an apocalyptic number.

It is an amenable number.

6479872781 is a deficient number, since it is larger than the sum of its proper divisors (224729899).

6479872781 is a wasteful number, since it uses less digits than its factorization.

6479872781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42895.

The product of its digits is 9483264, while the sum is 59.

The square root of 6479872781 is about 80497.6569907473. The cubic root of 6479872781 is about 1864.3273029057.

The spelling of 6479872781 in words is "six billion, four hundred seventy-nine million, eight hundred seventy-two thousand, seven hundred eighty-one".