51431350513 has 4 divisors (see below), whose sum is σ = 53090426368. Its totient is φ = 49772274660.

The previous prime is 51431350507. The next prime is 51431350519. The reversal of 51431350513 is 31505313415.

51431350513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (51431350507) and next prime (51431350519).

It is a cyclic number.

It is not a de Polignac number, because 51431350513 - 2²¹ = 51429253361 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 1659075823 = 51431350513 / (5 + 1 + 4 + 3 + 1 + 3 + 5 + 0 + 5 + 1 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51431350519) 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, 829537881 + ... + 829537942.

It is an arithmetic number, because the mean of its divisors is an integer number (13272606592).

Almost surely, 2^51431350513 is an apocalyptic number.

It is an amenable number.

51431350513 is a deficient number, since it is larger than the sum of its proper divisors (1659075855).

51431350513 is a wasteful number, since it uses less digits than its factorization.

51431350513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1659075854.

The product of its (nonzero) digits is 13500, while the sum is 31.

Adding to 51431350513 its reverse (31505313415), we get a palindrome (82936663928).

The spelling of 51431350513 in words is "fifty-one billion, four hundred thirty-one million, three hundred fifty thousand, five hundred thirteen".