171156123273661 has 2 divisors, whose sum is σ = 171156123273662. Its totient is φ = 171156123273660.

The previous prime is 171156123273607. The next prime is 171156123273673. The reversal of 171156123273661 is 166372321651171.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 89968905217636 + 81187218056025 = 9485194^2 + 9010395^2 .

It is a cyclic number.

It is not a de Polignac number, because 171156123273661 - 2²³ = 171156114885053 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 171156123273599 and 171156123273608.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171156126273661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85578061636830 + 85578061636831.

It is an arithmetic number, because the mean of its divisors is an integer number (85578061636831).

Almost surely, 2^{171156123273661} is an apocalyptic number.

It is an amenable number.

171156123273661 is a deficient number, since it is larger than the sum of its proper divisors (1).

171156123273661 is an equidigital number, since it uses as much as digits as its factorization.

171156123273661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1905120, while the sum is 52.

The spelling of 171156123273661 in words is "one hundred seventy-one trillion, one hundred fifty-six billion, one hundred twenty-three million, two hundred seventy-three thousand, six hundred sixty-one".