66550441949 has 2 divisors, whose sum is σ = 66550441950. Its totient is φ = 66550441948.

The previous prime is 66550441921. The next prime is 66550441957. The reversal of 66550441949 is 94914405566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65795841049 + 754600900 = 256507^2 + 27470^2 .

It is a cyclic number.

It is not a de Polignac number, because 66550441949 - 2¹² = 66550437853 is a prime.

It is a super-2 number, since 2×66550441949² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66550441949.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66550447949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33275220974 + 33275220975.

It is an arithmetic number, because the mean of its divisors is an integer number (33275220975).

Almost surely, 2^66550441949 is an apocalyptic number.

It is an amenable number.

66550441949 is a deficient number, since it is larger than the sum of its proper divisors (1).

66550441949 is an equidigital number, since it uses as much as digits as its factorization.

66550441949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4665600, while the sum is 53.

The spelling of 66550441949 in words is "sixty-six billion, five hundred fifty million, four hundred forty-one thousand, nine hundred forty-nine".