51191826191 has 4 divisors (see below), whose sum is σ = 55845628584. Its totient is φ = 46538023800.

The previous prime is 51191826167. The next prime is 51191826199. The reversal of 51191826191 is 19162819115.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51191826191 - 2²⁶ = 51124717327 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51191826199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2326901180 + ... + 2326901201.

It is an arithmetic number, because the mean of its divisors is an integer number (13961407146).

Almost surely, 2^51191826191 is an apocalyptic number.

51191826191 is a deficient number, since it is larger than the sum of its proper divisors (4653802393).

51191826191 is a wasteful number, since it uses less digits than its factorization.

51191826191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4653802392.

The product of its digits is 38880, while the sum is 44.

The spelling of 51191826191 in words is "fifty-one billion, one hundred ninety-one million, eight hundred twenty-six thousand, one hundred ninety-one".