21116150664491 has 2 divisors, whose sum is σ = 21116150664492. Its totient is φ = 21116150664490.

The previous prime is 21116150664451. The next prime is 21116150664503. The reversal of 21116150664491 is 19446605161112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21116150664491 is a prime.

It is not a weakly prime, because it can be changed into another prime (21116150664451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10558075332245 + 10558075332246.

It is an arithmetic number, because the mean of its divisors is an integer number (10558075332246).

Almost surely, 2^{21116150664491} is an apocalyptic number.

21116150664491 is a deficient number, since it is larger than the sum of its proper divisors (1).

21116150664491 is an equidigital number, since it uses as much as digits as its factorization.

21116150664491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 311040, while the sum is 47.

The spelling of 21116150664491 in words is "twenty-one trillion, one hundred sixteen billion, one hundred fifty million, six hundred sixty-four thousand, four hundred ninety-one".