51431323531 has 4 divisors (see below), whose sum is σ = 58778655472. Its totient is φ = 44083991592.

The previous prime is 51431323457. The next prime is 51431323561. The reversal of 51431323531 is 13532313415.

It is a happy number.

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 51431323531 - 2¹³ = 51431315339 is a prime.

It is a super-2 number, since 2×51431323531² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51431323493 and 51431323502.

It is not an unprimeable number, because it can be changed into a prime (51431323561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3673665960 + ... + 3673665973.

It is an arithmetic number, because the mean of its divisors is an integer number (14694663868).

Almost surely, 2^51431323531 is an apocalyptic number.

51431323531 is a deficient number, since it is larger than the sum of its proper divisors (7347331941).

51431323531 is an equidigital number, since it uses as much as digits as its factorization.

51431323531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7347331940.

The product of its digits is 16200, while the sum is 31.

Adding to 51431323531 its reverse (13532313415), we get a palindrome (64963636946).

The spelling of 51431323531 in words is "fifty-one billion, four hundred thirty-one million, three hundred twenty-three thousand, five hundred thirty-one".