21583066837 has 2 divisors, whose sum is σ = 21583066838. Its totient is φ = 21583066836.

The previous prime is 21583066793. The next prime is 21583066849. The reversal of 21583066837 is 73866038512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21538791121 + 44275716 = 146761^2 + 6654^2 .

It is a cyclic number.

It is not a de Polignac number, because 21583066837 - 2¹⁹ = 21582542549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21583066867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10791533418 + 10791533419.

It is an arithmetic number, because the mean of its divisors is an integer number (10791533419).

Almost surely, 2^21583066837 is an apocalyptic number.

It is an amenable number.

21583066837 is a deficient number, since it is larger than the sum of its proper divisors (1).

21583066837 is an equidigital number, since it uses as much as digits as its factorization.

21583066837 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1451520, while the sum is 49.

The spelling of 21583066837 in words is "twenty-one billion, five hundred eighty-three million, sixty-six thousand, eight hundred thirty-seven".