51191821089 has 12 divisors (see below), whose sum is σ = 74774571300. Its totient is φ = 33744420864.

The previous prime is 51191821039. The next prime is 51191821097. The reversal of 51191821089 is 98012819115.

51191821089 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 2 ways, for example, as 29528985600 + 21662835489 = 171840^2 + 147183^2 .

It is not a de Polignac number, because 51191821089 - 2⁹ = 51191820577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51191821039) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31954144 + ... + 31955745.

It is an arithmetic number, because the mean of its divisors is an integer number (6231214275).

Almost surely, 2^51191821089 is an apocalyptic number.

It is an amenable number.

51191821089 is a deficient number, since it is larger than the sum of its proper divisors (23582750211).

51191821089 is a wasteful number, since it uses less digits than its factorization.

51191821089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63909984 (or 63909981 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 45.

The spelling of 51191821089 in words is "fifty-one billion, one hundred ninety-one million, eight hundred twenty-one thousand, eighty-nine".