194528609821 has 48 divisors (see below), whose sum is σ = 247292060400. Its totient is φ = 151645519872.

The previous prime is 194528609819. The next prime is 194528609839. The reversal of 194528609821 is 128906825491.

194528609821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 110044792900 + 84483816921 = 331730^2 + 290661^2 .

It is not a de Polignac number, because 194528609821 - 2¹ = 194528609819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (194528609861) 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 47 ways as a sum of consecutive naturals, for example, 65518425 + ... + 65521393.

It is an arithmetic number, because the mean of its divisors is an integer number (5151917925).

Almost surely, 2^194528609821 is an apocalyptic number.

It is an amenable number.

194528609821 is a deficient number, since it is larger than the sum of its proper divisors (52763450579).

194528609821 is a wasteful number, since it uses less digits than its factorization.

194528609821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4478 (or 4471 counting only the distinct ones).

The product of its (nonzero) digits is 2488320, while the sum is 55.

The spelling of 194528609821 in words is "one hundred ninety-four billion, five hundred twenty-eight million, six hundred nine thousand, eight hundred twenty-one".