51306222 has 32 divisors (see below), whose sum is σ = 112840704. Its totient is φ = 15422400.

The previous prime is 51306197. The next prime is 51306239. The reversal of 51306222 is 22260315.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5322 + ... + 11442.

It is an arithmetic number, because the mean of its divisors is an integer number (3526272).

Almost surely, 2^51306222 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51306222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56420352).

51306222 is an abundant number, since it is smaller than the sum of its proper divisors (61534482).

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

51306222 is a wasteful number, since it uses less digits than its factorization.

51306222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6264.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 51306222 is about 7162.8361701214. The cubic root of 51306222 is about 371.5837203769.

Adding to 51306222 its reverse (22260315), we get a palindrome (73566537).

The spelling of 51306222 in words is "fifty-one million, three hundred six thousand, two hundred twenty-two".