16660100491 has 2 divisors, whose sum is σ = 16660100492. Its totient is φ = 16660100490.

The previous prime is 16660100489. The next prime is 16660100551. The reversal of 16660100491 is 19400106661.

It is a happy number.

16660100491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16660100491 - 2¹ = 16660100489 is a prime.

Together with 16660100489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16660100291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8330050245 + 8330050246.

It is an arithmetic number, because the mean of its divisors is an integer number (8330050246).

Almost surely, 2^16660100491 is an apocalyptic number.

16660100491 is a deficient number, since it is larger than the sum of its proper divisors (1).

16660100491 is an equidigital number, since it uses as much as digits as its factorization.

16660100491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The spelling of 16660100491 in words is "sixteen billion, six hundred sixty million, one hundred thousand, four hundred ninety-one".