51121216 has 28 divisors (see below), whose sum is σ = 102737920. Its totient is φ = 25234560.

The previous prime is 51121163. The next prime is 51121237. The reversal of 51121216 is 61212115.

51121216 is a nontrivial binomial coefficient, being equal to C(10112, 2).

It is a super-2 number, since 2×51121216² = 5226757450637312, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 51121193 and 51121202.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1 + ... + 10111.

Almost surely, 2^51121216 is an apocalyptic number.

51121216 is the 10111-st triangular number and also the 5056-th hexagonal number.

51121216 is the 3371-st centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51121216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51368960).

51121216 is an abundant number, since it is smaller than the sum of its proper divisors (51616704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51121216 is a wasteful number, since it uses less digits than its factorization.

51121216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10202 (or 10192 counting only the distinct ones).

The product of its digits is 120, while the sum is 19.

The square root of 51121216 is about 7149.9102092264. The cubic root of 51121216 is about 371.1365490536.

It can be divided in two parts, 5112 and 1216, that added together give a triangular number (6328 = T₁₁₂).

The spelling of 51121216 in words is "fifty-one million, one hundred twenty-one thousand, two hundred sixteen".