51211481 has 2 divisors, whose sum is σ = 51211482. Its totient is φ = 51211480.

The previous prime is 51211451. The next prime is 51211507. The reversal of 51211481 is 18411215.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47389456 + 3822025 = 6884^2 + 1955^2 .

It is a cyclic number.

It is not a de Polignac number, because 51211481 - 2¹⁰ = 51210457 is a prime.

It is a super-2 number, since 2×51211481² = 5245231572426722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51211421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25605740 + 25605741.

It is an arithmetic number, because the mean of its divisors is an integer number (25605741).

Almost surely, 2^51211481 is an apocalyptic number.

It is an amenable number.

51211481 is a deficient number, since it is larger than the sum of its proper divisors (1).

51211481 is an equidigital number, since it uses as much as digits as its factorization.

51211481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 320, while the sum is 23.

The square root of 51211481 is about 7156.2197422941. The cubic root of 51211481 is about 371.3548598654.

Adding to 51211481 its reverse (18411215), we get a palindrome (69622696).

The spelling of 51211481 in words is "fifty-one million, two hundred eleven thousand, four hundred eighty-one".