66121873 has 2 divisors, whose sum is σ = 66121874. Its totient is φ = 66121872.

The previous prime is 66121871. The next prime is 66121877. The reversal of 66121873 is 37812166.

66121873 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58186384 + 7935489 = 7628^2 + 2817^2 .

It is a cyclic number.

It is not a de Polignac number, because 66121873 - 2¹ = 66121871 is a prime.

Together with 66121871, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66121871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33060936 + 33060937.

It is an arithmetic number, because the mean of its divisors is an integer number (33060937).

Almost surely, 2^66121873 is an apocalyptic number.

It is an amenable number.

66121873 is a deficient number, since it is larger than the sum of its proper divisors (1).

66121873 is an equidigital number, since it uses as much as digits as its factorization.

66121873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 34.

The square root of 66121873 is about 8131.5357098152. The cubic root of 66121873 is about 404.3725955980.

The spelling of 66121873 in words is "sixty-six million, one hundred twenty-one thousand, eight hundred seventy-three".