15506022821 has 2 divisors, whose sum is σ = 15506022822. Its totient is φ = 15506022820.

The previous prime is 15506022799. The next prime is 15506022827. The reversal of 15506022821 is 12822060551.

15506022821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9744453796 + 5761569025 = 98714^2 + 75905^2 .

It is a cyclic number.

It is not a de Polignac number, because 15506022821 - 2¹⁴ = 15506006437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15506022827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7753011410 + 7753011411.

It is an arithmetic number, because the mean of its divisors is an integer number (7753011411).

Almost surely, 2^15506022821 is an apocalyptic number.

It is an amenable number.

15506022821 is a deficient number, since it is larger than the sum of its proper divisors (1).

15506022821 is an equidigital number, since it uses as much as digits as its factorization.

15506022821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9600, while the sum is 32.

The spelling of 15506022821 in words is "fifteen billion, five hundred six million, twenty-two thousand, eight hundred twenty-one".