51353221 has 4 divisors (see below), whose sum is σ = 51367744. Its totient is φ = 51338700.

The previous prime is 51353191. The next prime is 51353249. The reversal of 51353221 is 12235315.

51353221 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 a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 51353221 - 2¹⁵ = 51320453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51353192 and 51353201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51353251) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 1876 + ... + 10306.

It is an arithmetic number, because the mean of its divisors is an integer number (12841936).

Almost surely, 2^51353221 is an apocalyptic number.

It is an amenable number.

51353221 is a deficient number, since it is larger than the sum of its proper divisors (14523).

51353221 is an equidigital number, since it uses as much as digits as its factorization.

51353221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14522.

The product of its digits is 900, while the sum is 22.

The square root of 51353221 is about 7166.1161726559. The cubic root of 51353221 is about 371.6971486816.

Adding to 51353221 its reverse (12235315), we get a palindrome (63588536).

The spelling of 51353221 in words is "fifty-one million, three hundred fifty-three thousand, two hundred twenty-one".