1555156661099 has 2 divisors, whose sum is σ = 1555156661100. Its totient is φ = 1555156661098.

The previous prime is 1555156661063. The next prime is 1555156661119. The reversal of 1555156661099 is 9901666515551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1555156661099 - 2³⁶ = 1486437184363 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1555156651099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 777578330549 + 777578330550.

It is an arithmetic number, because the mean of its divisors is an integer number (777578330550).

Almost surely, 2^{1555156661099} is an apocalyptic number.

1555156661099 is a deficient number, since it is larger than the sum of its proper divisors (1).

1555156661099 is an equidigital number, since it uses as much as digits as its factorization.

1555156661099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10935000, while the sum is 59.

The spelling of 1555156661099 in words is "one trillion, five hundred fifty-five billion, one hundred fifty-six million, six hundred sixty-one thousand, ninety-nine".