51223345021 has 2 divisors, whose sum is σ = 51223345022. Its totient is φ = 51223345020.

The previous prime is 51223345001. The next prime is 51223345049. The reversal of 51223345021 is 12054332215.

It is an a-pointer prime, because the next prime (51223345049) can be obtained adding 51223345021 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45183879225 + 6039465796 = 212565^2 + 77714^2 .

It is a cyclic number.

It is not a de Polignac number, because 51223345021 - 2¹⁵ = 51223312253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51223345001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25611672510 + 25611672511.

It is an arithmetic number, because the mean of its divisors is an integer number (25611672511).

Almost surely, 2^51223345021 is an apocalyptic number.

It is an amenable number.

51223345021 is a deficient number, since it is larger than the sum of its proper divisors (1).

51223345021 is an equidigital number, since it uses as much as digits as its factorization.

51223345021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 51223345021 its reverse (12054332215), we get a palindrome (63277677236).

The spelling of 51223345021 in words is "fifty-one billion, two hundred twenty-three million, three hundred forty-five thousand, twenty-one".