51566643111 has 4 divisors (see below), whose sum is σ = 68755524152. Its totient is φ = 34377762072.

The previous prime is 51566643071. The next prime is 51566643113. The reversal of 51566643111 is 11134666515.

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

It is not a de Polignac number, because 51566643111 - 2¹⁰ = 51566642087 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 51566643111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51566643113) 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, 8594440516 + ... + 8594440521.

It is an arithmetic number, because the mean of its divisors is an integer number (17188881038).

Almost surely, 2^51566643111 is an apocalyptic number.

51566643111 is a deficient number, since it is larger than the sum of its proper divisors (17188881041).

51566643111 is a wasteful number, since it uses less digits than its factorization.

51566643111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17188881040.

The product of its digits is 64800, while the sum is 39.

The spelling of 51566643111 in words is "fifty-one billion, five hundred sixty-six million, six hundred forty-three thousand, one hundred eleven".