51305513 has 4 divisors (see below), whose sum is σ = 58634880. Its totient is φ = 43976148.

The previous prime is 51305483. The next prime is 51305521. The reversal of 51305513 is 31550315.

51305513 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 a cyclic number.

It is not a de Polignac number, because 51305513 - 2⁸ = 51305257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51365513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3664673 + ... + 3664686.

It is an arithmetic number, because the mean of its divisors is an integer number (14658720).

Almost surely, 2^51305513 is an apocalyptic number.

It is an amenable number.

51305513 is a deficient number, since it is larger than the sum of its proper divisors (7329367).

51305513 is an equidigital number, since it uses as much as digits as its factorization.

51305513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7329366.

The product of its (nonzero) digits is 1125, while the sum is 23.

The square root of 51305513 is about 7162.7866783815. The cubic root of 51305513 is about 371.5820087322.

Adding to 51305513 its reverse (31550315), we get a palindrome (82855828).

The spelling of 51305513 in words is "fifty-one million, three hundred five thousand, five hundred thirteen".