51512222 has 16 divisors (see below), whose sum is σ = 78404544. Its totient is φ = 25380000.

The previous prime is 51512189. The next prime is 51512233. The reversal of 51512222 is 22221515.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 51512194 and 51512203.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54272 + ... + 55212.

It is an arithmetic number, because the mean of its divisors is an integer number (4900284).

Almost surely, 2^51512222 is an apocalyptic number.

51512222 is a deficient number, since it is larger than the sum of its proper divisors (26892322).

51512222 is a wasteful number, since it uses less digits than its factorization.

51512222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315.

The product of its digits is 400, while the sum is 20.

The square root of 51512222 is about 7177.2015437774. The cubic root of 51512222 is about 372.0803724670.

Adding to 51512222 its reverse (22221515), we get a palindrome (73733737).

The spelling of 51512222 in words is "fifty-one million, five hundred twelve thousand, two hundred twenty-two".