66542554399 has 2 divisors, whose sum is σ = 66542554400. Its totient is φ = 66542554398.

The previous prime is 66542554381. The next prime is 66542554423. The reversal of 66542554399 is 99345524566.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66542554399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66542552399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33271277199 + 33271277200.

It is an arithmetic number, because the mean of its divisors is an integer number (33271277200).

Almost surely, 2^66542554399 is an apocalyptic number.

66542554399 is a deficient number, since it is larger than the sum of its proper divisors (1).

66542554399 is an equidigital number, since it uses as much as digits as its factorization.

66542554399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992000, while the sum is 58.

The spelling of 66542554399 in words is "sixty-six billion, five hundred forty-two million, five hundred fifty-four thousand, three hundred ninety-nine".