187128027561 has 16 divisors (see below), whose sum is σ = 264295225728. Its totient is φ = 117362784000.

The previous prime is 187128027451. The next prime is 187128027571. The reversal of 187128027561 is 165720821781.

187128027561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 187128027561 - 2³⁰ = 186054285737 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 187128027561.

It is not an unprimeable number, because it can be changed into a prime (187128027571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 675990 + ... + 911711.

It is an arithmetic number, because the mean of its divisors is an integer number (16518451608).

Almost surely, 2^187128027561 is an apocalyptic number.

It is an amenable number.

187128027561 is a deficient number, since it is larger than the sum of its proper divisors (77167198167).

187128027561 is a wasteful number, since it uses less digits than its factorization.

187128027561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1590032.

The product of its (nonzero) digits is 376320, while the sum is 48.

The spelling of 187128027561 in words is "one hundred eighty-seven billion, one hundred twenty-eight million, twenty-seven thousand, five hundred sixty-one".