1555154240161 has 2 divisors, whose sum is σ = 1555154240162. Its totient is φ = 1555154240160.

The previous prime is 1555154240119. The next prime is 1555154240177. The reversal of 1555154240161 is 1610424515551.

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., 1249476840000 + 305677400161 = 1117800^2 + 552881^2 .

It is a cyclic number.

It is not a de Polignac number, because 1555154240161 - 2⁹ = 1555154239649 is a prime.

It is not a weakly prime, because it can be changed into another prime (1555154240191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 777577120080 + 777577120081.

It is an arithmetic number, because the mean of its divisors is an integer number (777577120081).

Almost surely, 2^{1555154240161} is an apocalyptic number.

It is an amenable number.

1555154240161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1555154240161 is an equidigital number, since it uses as much as digits as its factorization.

1555154240161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120000, while the sum is 40.

The spelling of 1555154240161 in words is "one trillion, five hundred fifty-five billion, one hundred fifty-four million, two hundred forty thousand, one hundred sixty-one".