155506656161 has 2 divisors, whose sum is σ = 155506656162. Its totient is φ = 155506656160.

The previous prime is 155506656049. The next prime is 155506656167. The reversal of 155506656161 is 161656605551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134894598400 + 20612057761 = 367280^2 + 143569^2 .

It is a cyclic number.

It is not a de Polignac number, because 155506656161 - 2²⁶ = 155439547297 is a prime.

It is a super-2 number, since 2×155506656161² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (155506656167) 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, 77753328080 + 77753328081.

It is an arithmetic number, because the mean of its divisors is an integer number (77753328081).

Almost surely, 2^155506656161 is an apocalyptic number.

It is an amenable number.

155506656161 is a deficient number, since it is larger than the sum of its proper divisors (1).

155506656161 is an equidigital number, since it uses as much as digits as its factorization.

155506656161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 810000, while the sum is 47.

The spelling of 155506656161 in words is "one hundred fifty-five billion, five hundred six million, six hundred fifty-six thousand, one hundred sixty-one".