21155164344871 has 2 divisors, whose sum is σ = 21155164344872. Its totient is φ = 21155164344870.

The previous prime is 21155164344851. The next prime is 21155164344877. The reversal of 21155164344871 is 17844346155112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21155164344871 - 2⁹ = 21155164344359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21155164344877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577582172435 + 10577582172436.

It is an arithmetic number, because the mean of its divisors is an integer number (10577582172436).

Almost surely, 2^{21155164344871} is an apocalyptic number.

21155164344871 is a deficient number, since it is larger than the sum of its proper divisors (1).

21155164344871 is an equidigital number, since it uses as much as digits as its factorization.

21155164344871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3225600, while the sum is 52.

The spelling of 21155164344871 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred sixty-four million, three hundred forty-four thousand, eight hundred seventy-one".