188563509121 has 9 divisors (see below), whose sum is σ = 204190267779. Its totient is φ = 174053412936.

The previous prime is 188563509119. The next prime is 188563509157. The reversal of 188563509121 is 121905365881.

The square root of 188563509121 is 434239.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 27894010225 + 160669498896 = 167015^2 + 400836^2 .

It is not a de Polignac number, because 188563509121 - 2¹ = 188563509119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (188563509521) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5628406 + ... + 5661808.

It is an arithmetic number, because the mean of its divisors is an integer number (22687807531).

Almost surely, 2^188563509121 is an apocalyptic number.

188563509121 is the 434239-th square number.

188563509121 is the 217120-th centered octagonal number.

It is an amenable number.

188563509121 is a deficient number, since it is larger than the sum of its proper divisors (15626758658).

188563509121 is an frugal number, since it uses more digits than its factorization.

188563509121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66832 (or 33416 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 49.

Multiplying 188563509121 by its sum of digits (49), we get a square (9239611946929 = 3039673²).

The spelling of 188563509121 in words is "one hundred eighty-eight billion, five hundred sixty-three million, five hundred nine thousand, one hundred twenty-one".