51511656111 has 4 divisors (see below), whose sum is σ = 68682208152. Its totient is φ = 34341104072.

The previous prime is 51511656073. The next prime is 51511656121. The reversal of 51511656111 is 11165611515.

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 51511656111 - 2¹¹ = 51511654063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51511656121) 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, 8585276016 + ... + 8585276021.

It is an arithmetic number, because the mean of its divisors is an integer number (17170552038).

Almost surely, 2^51511656111 is an apocalyptic number.

51511656111 is a deficient number, since it is larger than the sum of its proper divisors (17170552041).

51511656111 is a wasteful number, since it uses less digits than its factorization.

51511656111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17170552040.

The product of its digits is 4500, while the sum is 33.

The spelling of 51511656111 in words is "fifty-one billion, five hundred eleven million, six hundred fifty-six thousand, one hundred eleven".