18446840466991 has 2 divisors, whose sum is σ = 18446840466992. Its totient is φ = 18446840466990.

The previous prime is 18446840466959. The next prime is 18446840467009. The reversal of 18446840466991 is 19966404864481.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18446840466991 - 2⁵ = 18446840466959 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18446840466991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18446840466091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9223420233495 + 9223420233496.

It is an arithmetic number, because the mean of its divisors is an integer number (9223420233496).

Almost surely, 2^{18446840466991} is an apocalyptic number.

18446840466991 is a deficient number, since it is larger than the sum of its proper divisors (1).

18446840466991 is an equidigital number, since it uses as much as digits as its factorization.

18446840466991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 286654464, while the sum is 70.

The spelling of 18446840466991 in words is "eighteen trillion, four hundred forty-six billion, eight hundred forty million, four hundred sixty-six thousand, nine hundred ninety-one".