51431111 has 4 divisors (see below), whose sum is σ = 51586824. Its totient is φ = 51275400.

The previous prime is 51431099. The next prime is 51431131. The reversal of 51431111 is 11113415.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11113415 = 5 ⋅2222683.

It is a cyclic number.

It is not a de Polignac number, because 51431111 - 2⁶ = 51431047 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 51431111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51431131) 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, 77360 + ... + 78021.

It is an arithmetic number, because the mean of its divisors is an integer number (12896706).

Almost surely, 2^51431111 is an apocalyptic number.

51431111 is a deficient number, since it is larger than the sum of its proper divisors (155713).

51431111 is a wasteful number, since it uses less digits than its factorization.

51431111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155712.

The product of its digits is 60, while the sum is 17.

The square root of 51431111 is about 7171.5487169788. The cubic root of 51431111 is about 371.8849776387.

Adding to 51431111 its reverse (11113415), we get a palindrome (62544526).

The spelling of 51431111 in words is "fifty-one million, four hundred thirty-one thousand, one hundred eleven".