660066701557 has 2 divisors, whose sum is σ = 660066701558. Its totient is φ = 660066701556.

The previous prime is 660066701551. The next prime is 660066701579. The reversal of 660066701557 is 755107660066.

It is a happy number.

660066701557 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., 660057128721 + 9572836 = 812439^2 + 3094^2 .

It is a cyclic number.

It is not a de Polignac number, because 660066701557 - 2³ = 660066701549 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 660066701557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (660066701551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330033350778 + 330033350779.

It is an arithmetic number, because the mean of its divisors is an integer number (330033350779).

Almost surely, 2^660066701557 is an apocalyptic number.

It is an amenable number.

660066701557 is a deficient number, since it is larger than the sum of its proper divisors (1).

660066701557 is an equidigital number, since it uses as much as digits as its factorization.

660066701557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1587600, while the sum is 49.

The spelling of 660066701557 in words is "six hundred sixty billion, sixty-six million, seven hundred one thousand, five hundred fifty-seven".