666783772191 has 12 divisors (see below), whose sum is σ = 963281545200. Its totient is φ = 444453547200.

The previous prime is 666783772183. The next prime is 666783772199. The reversal of 666783772191 is 191277387666.

It is an interprime number because it is at equal distance from previous prime (666783772183) and next prime (666783772199).

It is not a de Polignac number, because 666783772191 - 2³ = 666783772183 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666783772199) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5686035 + ... + 5802116.

It is an arithmetic number, because the mean of its divisors is an integer number (80273462100).

Almost surely, 2^666783772191 is an apocalyptic number.

666783772191 is a deficient number, since it is larger than the sum of its proper divisors (296497773009).

666783772191 is a wasteful number, since it uses less digits than its factorization.

666783772191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11494606 (or 11494603 counting only the distinct ones).

The product of its digits is 32006016, while the sum is 63.

The spelling of 666783772191 in words is "six hundred sixty-six billion, seven hundred eighty-three million, seven hundred seventy-two thousand, one hundred ninety-one".