188389853521 has 3 divisors (see below), whose sum is σ = 188390287561. Its totient is φ = 188389419482.

The previous prime is 188389853501. The next prime is 188389853537. The reversal of 188389853521 is 125358983881.

The square root of 188389853521 is 434039.

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

188389853521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 125358983881 = 47 ⋅2667212423.

It is not a de Polignac number, because 188389853521 - 2⁹ = 188389853009 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 188389853521.

It is not an unprimeable number, because it can be changed into a prime (188389853501) 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 2 ways as a sum of consecutive naturals, for example, 217020 + ... + 651058.

Almost surely, 2^188389853521 is an apocalyptic number.

188389853521 is the 434039-th square number.

188389853521 is the 217020-th centered octagonal number.

It is an amenable number.

188389853521 is a deficient number, since it is larger than the sum of its proper divisors (434040).

188389853521 is an frugal number, since it uses more digits than its factorization.

188389853521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868078 (or 434039 counting only the distinct ones).

The product of its digits is 16588800, while the sum is 61.

The spelling of 188389853521 in words is "one hundred eighty-eight billion, three hundred eighty-nine million, eight hundred fifty-three thousand, five hundred twenty-one".