51431121 has 12 divisors (see below), whose sum is σ = 84902272. Its totient is φ = 29389176.

The previous prime is 51431099. The next prime is 51431131. The reversal of 51431121 is 12113415.

51431121 is a `hidden beast` number, since 514 + 31 + 121 = 666.

It is not a de Polignac number, because 51431121 - 2⁵ = 51431089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 51431094 and 51431103.

It is not an unprimeable number, because it can be changed into a prime (51431131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 408121 + ... + 408246.

Almost surely, 2^51431121 is an apocalyptic number.

It is an amenable number.

51431121 is a deficient number, since it is larger than the sum of its proper divisors (33471151).

51431121 is a wasteful number, since it uses less digits than its factorization.

51431121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816380 (or 816377 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 51431121 is about 7171.5494141782. The cubic root of 51431121 is about 371.8850017412.

Adding to 51431121 its reverse (12113415), we get a palindrome (63544536).

The spelling of 51431121 in words is "fifty-one million, four hundred thirty-one thousand, one hundred twenty-one".