6634166781 has 16 divisors (see below), whose sum is σ = 9781888320. Its totient is φ = 3965627520.

The previous prime is 6634166779. The next prime is 6634166831. The reversal of 6634166781 is 1876614366.

It is not a de Polignac number, because 6634166781 - 2¹ = 6634166779 is a prime.

It is a super-2 number, since 2×6634166781² = 88024337756247803922, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 6634166781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6634166761) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1374546 + ... + 1379363.

It is an arithmetic number, because the mean of its divisors is an integer number (611368020).

Almost surely, 2^6634166781 is an apocalyptic number.

It is an amenable number.

6634166781 is a deficient number, since it is larger than the sum of its proper divisors (3147721539).

6634166781 is a wasteful number, since it uses less digits than its factorization.

6634166781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2753996.

The product of its digits is 870912, while the sum is 48.

The square root of 6634166781 is about 81450.3946030957. The cubic root of 6634166781 is about 1879.0087181121.

The spelling of 6634166781 in words is "six billion, six hundred thirty-four million, one hundred sixty-six thousand, seven hundred eighty-one".