51424221 has 16 divisors (see below), whose sum is σ = 71424000. Its totient is φ = 32870208.

The previous prime is 51424211. The next prime is 51424229. The reversal of 51424221 is 12242415.

It is not a de Polignac number, because 51424221 - 2⁵ = 51424189 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51424229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10980 + ... + 14946.

It is an arithmetic number, because the mean of its divisors is an integer number (4464000).

Almost surely, 2^51424221 is an apocalyptic number.

It is an amenable number.

51424221 is a deficient number, since it is larger than the sum of its proper divisors (19999779).

51424221 is a wasteful number, since it uses less digits than its factorization.

51424221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4148.

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

The square root of 51424221 is about 7171.0683304512. The cubic root of 51424221 is about 371.8683702982.

Adding to 51424221 its reverse (12242415), we get a palindrome (63666636).

The spelling of 51424221 in words is "fifty-one million, four hundred twenty-four thousand, two hundred twenty-one".