666553346140401 has 16 divisors (see below), whose sum is σ = 987487220185600. Its totient is φ = 444368545770384.

The previous prime is 666553346140397. The next prime is 666553346140447. The reversal of 666553346140401 is 104041643355666.

It is a happy number.

It is not a de Polignac number, because 666553346140401 - 2² = 666553346140397 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666553346140501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27578055 + ... + 45756483.

It is an arithmetic number, because the mean of its divisors is an integer number (61717951261600).

Almost surely, 2^{666553346140401} is an apocalyptic number.

It is an amenable number.

666553346140401 is a deficient number, since it is larger than the sum of its proper divisors (320933874045199).

666553346140401 is a wasteful number, since it uses less digits than its factorization.

666553346140401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19536485 (or 19536479 counting only the distinct ones).

The product of its (nonzero) digits is 18662400, while the sum is 54.

The spelling of 666553346140401 in words is "six hundred sixty-six trillion, five hundred fifty-three billion, three hundred forty-six million, one hundred forty thousand, four hundred one".