19913591965171 has 2 divisors, whose sum is σ = 19913591965172. Its totient is φ = 19913591965170.

The previous prime is 19913591965121. The next prime is 19913591965207. The reversal of 19913591965171 is 17156919531991.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19913591965171 is a prime.

It is a super-2 number, since 2×19913591965171² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19913591965097 and 19913591965106.

It is not a weakly prime, because it can be changed into another prime (19913591965121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9956795982585 + 9956795982586.

It is an arithmetic number, because the mean of its divisors is an integer number (9956795982586).

Almost surely, 2^{19913591965171} is an apocalyptic number.

19913591965171 is a deficient number, since it is larger than the sum of its proper divisors (1).

19913591965171 is an equidigital number, since it uses as much as digits as its factorization.

19913591965171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20667150, while the sum is 67.

The spelling of 19913591965171 in words is "nineteen trillion, nine hundred thirteen billion, five hundred ninety-one million, nine hundred sixty-five thousand, one hundred seventy-one".