51313513 has 2 divisors, whose sum is σ = 51313514. Its totient is φ = 51313512.

The previous prime is 51313511. The next prime is 51313517. The reversal of 51313513 is 31531315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51151104 + 162409 = 7152^2 + 403^2 .

It is a cyclic number.

It is not a de Polignac number, because 51313513 - 2¹ = 51313511 is a prime.

Together with 51313511, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51313511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25656756 + 25656757.

It is an arithmetic number, because the mean of its divisors is an integer number (25656757).

Almost surely, 2^51313513 is an apocalyptic number.

It is an amenable number.

51313513 is a deficient number, since it is larger than the sum of its proper divisors (1).

51313513 is an equidigital number, since it uses as much as digits as its factorization.

51313513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 675, while the sum is 22.

The square root of 51313513 is about 7163.3450984858. The cubic root of 51313513 is about 371.6013211569.

Adding to 51313513 its reverse (31531315), we get a palindrome (82844828).

The spelling of 51313513 in words is "fifty-one million, three hundred thirteen thousand, five hundred thirteen".