51333521 has 4 divisors (see below), whose sum is σ = 52302132. Its totient is φ = 50364912.

The previous prime is 51333463. The next prime is 51333533. The reversal of 51333521 is 12533315.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 42719296 + 8614225 = 6536^2 + 2935^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51333521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51335521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 484226 + ... + 484331.

It is an arithmetic number, because the mean of its divisors is an integer number (13075533).

Almost surely, 2^51333521 is an apocalyptic number.

It is an amenable number.

51333521 is a deficient number, since it is larger than the sum of its proper divisors (968611).

51333521 is an equidigital number, since it uses as much as digits as its factorization.

51333521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 968610.

The product of its digits is 1350, while the sum is 23.

The square root of 51333521 is about 7164.7415166215. The cubic root of 51333521 is about 371.6496127450.

Adding to 51333521 its reverse (12533315), we get a palindrome (63866836).

The spelling of 51333521 in words is "fifty-one million, three hundred thirty-three thousand, five hundred twenty-one".