51313121 has 4 divisors (see below), whose sum is σ = 51460500. Its totient is φ = 51165744.

The previous prime is 51313081. The next prime is 51313127. The reversal of 51313121 is 12131315.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 41422096 + 9891025 = 6436^2 + 3145^2 .

It is a cyclic number.

It is not a de Polignac number, because 51313121 - 2¹⁰ = 51312097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 51313121.

It is not an unprimeable number, because it can be changed into a prime (51313127) 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, 73166 + ... + 73863.

It is an arithmetic number, because the mean of its divisors is an integer number (12865125).

Almost surely, 2^51313121 is an apocalyptic number.

It is an amenable number.

51313121 is a deficient number, since it is larger than the sum of its proper divisors (147379).

51313121 is a wasteful number, since it uses less digits than its factorization.

51313121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147378.

The product of its digits is 90, while the sum is 17.

The square root of 51313121 is about 7163.3177369149. The cubic root of 51313121 is about 371.6003748949.

Adding to 51313121 its reverse (12131315), we get a palindrome (63444436).

The spelling of 51313121 in words is "fifty-one million, three hundred thirteen thousand, one hundred twenty-one".