21171161715061 has 2 divisors, whose sum is σ = 21171161715062. Its totient is φ = 21171161715060.

The previous prime is 21171161715001. The next prime is 21171161715071. The reversal of 21171161715061 is 16051716117112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21165428348100 + 5733366961 = 4600590^2 + 75719^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21171161715061 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21171161715001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10585580857530 + 10585580857531.

It is an arithmetic number, because the mean of its divisors is an integer number (10585580857531).

Almost surely, 2^{21171161715061} is an apocalyptic number.

It is an amenable number.

21171161715061 is a deficient number, since it is larger than the sum of its proper divisors (1).

21171161715061 is an equidigital number, since it uses as much as digits as its factorization.

21171161715061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17640, while the sum is 40.

The spelling of 21171161715061 in words is "twenty-one trillion, one hundred seventy-one billion, one hundred sixty-one million, seven hundred fifteen thousand, sixty-one".