51731222 has 4 divisors (see below), whose sum is σ = 77596836. Its totient is φ = 25865610.

The previous prime is 51731203. The next prime is 51731237. The reversal of 51731222 is 22213715.

It is a happy number.

51731222 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 22213715 = 5 ⋅4442743.

It is a super-2 number, since 2×51731222² = 5352238659226568, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 12932804 + ... + 12932807.

It is an arithmetic number, because the mean of its divisors is an integer number (19399209).

Almost surely, 2^51731222 is an apocalyptic number.

51731222 is a deficient number, since it is larger than the sum of its proper divisors (25865614).

51731222 is a wasteful number, since it uses less digits than its factorization.

51731222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25865613.

The product of its digits is 840, while the sum is 23.

The square root of 51731222 is about 7192.4420053275. The cubic root of 51731222 is about 372.6069167441.

Adding to 51731222 its reverse (22213715), we get a palindrome (73944937).

The spelling of 51731222 in words is "fifty-one million, seven hundred thirty-one thousand, two hundred twenty-two".