2666103991 has 2 divisors, whose sum is σ = 2666103992. Its totient is φ = 2666103990.

The previous prime is 2666103989. The next prime is 2666104013. The reversal of 2666103991 is 1993016662.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2666103991 - 2¹ = 2666103989 is a prime.

It is a super-2 number, since 2×2666103991² = 14216220981652256162, which contains 22 as substring.

Together with 2666103989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2666103901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1333051995 + 1333051996.

It is an arithmetic number, because the mean of its divisors is an integer number (1333051996).

Almost surely, 2^2666103991 is an apocalyptic number.

2666103991 is a deficient number, since it is larger than the sum of its proper divisors (1).

2666103991 is an equidigital number, since it uses as much as digits as its factorization.

2666103991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 2666103991 is about 51634.3295782951. The cubic root of 2666103991 is about 1386.6250074611.

The spelling of 2666103991 in words is "two billion, six hundred sixty-six million, one hundred three thousand, nine hundred ninety-one".