21250225666171 has 2 divisors, whose sum is σ = 21250225666172. Its totient is φ = 21250225666170.

The previous prime is 21250225666147. The next prime is 21250225666261. The reversal of 21250225666171 is 17166652205212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21250225666171 - 2⁹ = 21250225665659 is a prime.

It is not a weakly prime, because it can be changed into another prime (21250225666141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10625112833085 + 10625112833086.

It is an arithmetic number, because the mean of its divisors is an integer number (10625112833086).

Almost surely, 2^{21250225666171} is an apocalyptic number.

21250225666171 is a deficient number, since it is larger than the sum of its proper divisors (1).

21250225666171 is an equidigital number, since it uses as much as digits as its factorization.

21250225666171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 21250225666171 in words is "twenty-one trillion, two hundred fifty billion, two hundred twenty-five million, six hundred sixty-six thousand, one hundred seventy-one".