66990198040481 has 2 divisors, whose sum is σ = 66990198040482. Its totient is φ = 66990198040480.

The previous prime is 66990198040477. The next prime is 66990198040607. The reversal of 66990198040481 is 18404089109966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66328645177600 + 661552862881 = 8144240^2 + 813359^2 .

It is a cyclic number.

It is not a de Polignac number, because 66990198040481 - 2² = 66990198040477 is a prime.

It is a super-2 number, since 2×66990198040481² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66990198045481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33495099020240 + 33495099020241.

It is an arithmetic number, because the mean of its divisors is an integer number (33495099020241).

Almost surely, 2^{66990198040481} is an apocalyptic number.

It is an amenable number.

66990198040481 is a deficient number, since it is larger than the sum of its proper divisors (1).

66990198040481 is an equidigital number, since it uses as much as digits as its factorization.

66990198040481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26873856, while the sum is 65.

The spelling of 66990198040481 in words is "sixty-six trillion, nine hundred ninety billion, one hundred ninety-eight million, forty thousand, four hundred eighty-one".