51721113 has 16 divisors (see below), whose sum is σ = 71409152. Its totient is φ = 33264000.

The previous prime is 51721099. The next prime is 51721127. The reversal of 51721113 is 31112715.

It is a happy number.

51721113 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51721099) and next prime (51721127).

It is not a de Polignac number, because 51721113 - 2¹⁰ = 51720089 is a prime.

It is a Smith number, since the sum of its digits (21) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51721113.

It is not an unprimeable number, because it can be changed into a prime (51721133) 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 15 ways as a sum of consecutive naturals, for example, 38493 + ... + 39813.

It is an arithmetic number, because the mean of its divisors is an integer number (4463072).

Almost surely, 2^51721113 is an apocalyptic number.

It is an amenable number.

51721113 is a deficient number, since it is larger than the sum of its proper divisors (19688039).

51721113 is a wasteful number, since it uses less digits than its factorization.

51721113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1776.

The product of its digits is 210, while the sum is 21.

The square root of 51721113 is about 7191.7392194100. The cubic root of 51721113 is about 372.5826443057.

Adding to 51721113 its reverse (31112715), we get a palindrome (82833828).

The spelling of 51721113 in words is "fifty-one million, seven hundred twenty-one thousand, one hundred thirteen".