51113531111 has 4 divisors (see below), whose sum is σ = 51117567552. Its totient is φ = 51109494672.

The previous prime is 51113531107. The next prime is 51113531173. The reversal of 51113531111 is 11113531115.

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 51113531111 - 2² = 51113531107 is a prime.

It is a super-2 number, since 2×51113531111² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51113561111) 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, 1999166 + ... + 2024571.

It is an arithmetic number, because the mean of its divisors is an integer number (12779391888).

Almost surely, 2^51113531111 is an apocalyptic number.

51113531111 is a deficient number, since it is larger than the sum of its proper divisors (4036441).

51113531111 is a wasteful number, since it uses less digits than its factorization.

51113531111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4036440.

The product of its digits is 225, while the sum is 23.

The spelling of 51113531111 in words is "fifty-one billion, one hundred thirteen million, five hundred thirty-one thousand, one hundred eleven".