51421224 has 16 divisors (see below), whose sum is σ = 128553120. Its totient is φ = 17140400.

The previous prime is 51421217. The next prime is 51421229. The reversal of 51421224 is 42212415.

It is a self number, because there is not a number n which added to its sum of digits gives 51421224.

It is not an unprimeable number, because it can be changed into a prime (51421229) by changing a digit.

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, 1071252 + ... + 1071299.

It is an arithmetic number, because the mean of its divisors is an integer number (8034570).

Almost surely, 2^51421224 is an apocalyptic number.

It is an amenable number.

51421224 is an abundant number, since it is smaller than the sum of its proper divisors (77131896).

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

51421224 is a wasteful number, since it uses less digits than its factorization.

51421224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2142560 (or 2142556 counting only the distinct ones).

The product of its digits is 640, while the sum is 21.

The square root of 51421224 is about 7170.8593627263. The cubic root of 51421224 is about 371.8611460037.

Adding to 51421224 its reverse (42212415), we get a palindrome (93633639).

The spelling of 51421224 in words is "fifty-one million, four hundred twenty-one thousand, two hundred twenty-four".