51211420 has 48 divisors (see below), whose sum is σ = 116339328. Its totient is φ = 18823680.

The previous prime is 51211387. The next prime is 51211421. The reversal of 51211420 is 2411215.

51211420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 51211394 and 51211403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51211421) 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, 111832 + ... + 112288.

It is an arithmetic number, because the mean of its divisors is an integer number (2423736).

Almost surely, 2^51211420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51211420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58169664).

51211420 is an abundant number, since it is smaller than the sum of its proper divisors (65127908).

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

51211420 is a wasteful number, since it uses less digits than its factorization.

51211420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910 (or 908 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 51211420 is about 7156.2154802661. The cubic root of 51211420 is about 371.3547124202.

Adding to 51211420 its reverse (2411215), we get a palindrome (53622635).

The spelling of 51211420 in words is "fifty-one million, two hundred eleven thousand, four hundred twenty".