51530321 has 2 divisors, whose sum is σ = 51530322. Its totient is φ = 51530320.

The previous prime is 51530293. The next prime is 51530329. The reversal of 51530321 is 12303515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43890625 + 7639696 = 6625^2 + 2764^2 .

It is a cyclic number.

It is not a de Polignac number, because 51530321 - 2¹⁰ = 51529297 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 51530293 and 51530302.

It is not a weakly prime, because it can be changed into another prime (51530329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25765160 + 25765161.

It is an arithmetic number, because the mean of its divisors is an integer number (25765161).

Almost surely, 2^51530321 is an apocalyptic number.

It is an amenable number.

51530321 is a deficient number, since it is larger than the sum of its proper divisors (1).

51530321 is an equidigital number, since it uses as much as digits as its factorization.

51530321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 51530321 is about 7178.4623005209. The cubic root of 51530321 is about 372.1239446126.

Adding to 51530321 its reverse (12303515), we get a palindrome (63833836).

The spelling of 51530321 in words is "fifty-one million, five hundred thirty thousand, three hundred twenty-one".