1205170155121 has 2 divisors, whose sum is σ = 1205170155122. Its totient is φ = 1205170155120.

The previous prime is 1205170155113. The next prime is 1205170155169. The reversal of 1205170155121 is 1215510715021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 694995664896 + 510174490225 = 833664^2 + 714265^2 .

It is a cyclic number.

It is not a de Polignac number, because 1205170155121 - 2³ = 1205170155113 is a prime.

It is not a weakly prime, because it can be changed into another prime (1205170155421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602585077560 + 602585077561.

It is an arithmetic number, because the mean of its divisors is an integer number (602585077561).

Almost surely, 2^{1205170155121} is an apocalyptic number.

It is an amenable number.

1205170155121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205170155121 is an equidigital number, since it uses as much as digits as its factorization.

1205170155121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3500, while the sum is 31.

The spelling of 1205170155121 in words is "one trillion, two hundred five billion, one hundred seventy million, one hundred fifty-five thousand, one hundred twenty-one".