6781906772 has 12 divisors (see below), whose sum is σ = 11917584756. Its totient is φ = 3376882560.

The previous prime is 6781906757. The next prime is 6781906837. The reversal of 6781906772 is 2776091876.

It can be written as a sum of positive squares in 2 ways, for example, as 5271340816 + 1510565956 = 72604^2 + 38866^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3516623 + ... + 3518550.

It is an arithmetic number, because the mean of its divisors is an integer number (993132063).

Almost surely, 2^6781906772 is an apocalyptic number.

It is an amenable number.

6781906772 is a deficient number, since it is larger than the sum of its proper divisors (5135677984).

6781906772 is a wasteful number, since it uses less digits than its factorization.

6781906772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7035418 (or 7035416 counting only the distinct ones).

The product of its (nonzero) digits is 1778112, while the sum is 53.

The square root of 6781906772 is about 82352.3331302763. Note that the first 3 decimals coincide. The cubic root of 6781906772 is about 1892.8546739993.

The spelling of 6781906772 in words is "six billion, seven hundred eighty-one million, nine hundred six thousand, seven hundred seventy-two".