51205513 has 16 divisors (see below), whose sum is σ = 58302720. Its totient is φ = 44672256.

The previous prime is 51205501. The next prime is 51205519. The reversal of 51205513 is 31550215.

It is a cyclic number.

It is not a de Polignac number, because 51205513 - 2⁵ = 51205481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51205519) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13495 + ... + 16867.

It is an arithmetic number, because the mean of its divisors is an integer number (3643920).

Almost surely, 2^51205513 is an apocalyptic number.

It is an amenable number.

51205513 is a deficient number, since it is larger than the sum of its proper divisors (7097207).

51205513 is a wasteful number, since it uses less digits than its factorization.

51205513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3456.

The product of its (nonzero) digits is 750, while the sum is 22.

The square root of 51205513 is about 7155.8027502161. The cubic root of 51205513 is about 371.3404338561.

Adding to 51205513 its reverse (31550215), we get a palindrome (82755728).

The spelling of 51205513 in words is "fifty-one million, two hundred five thousand, five hundred thirteen".