660921560287 has 2 divisors, whose sum is σ = 660921560288. Its totient is φ = 660921560286.

The previous prime is 660921560269. The next prime is 660921560293. The reversal of 660921560287 is 782065129066.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 660921560287 - 2³⁹ = 111165746399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (660921560267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330460780143 + 330460780144.

It is an arithmetic number, because the mean of its divisors is an integer number (330460780144).

Almost surely, 2^660921560287 is an apocalyptic number.

660921560287 is a deficient number, since it is larger than the sum of its proper divisors (1).

660921560287 is an equidigital number, since it uses as much as digits as its factorization.

660921560287 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2177280, while the sum is 52.

The spelling of 660921560287 in words is "six hundred sixty billion, nine hundred twenty-one million, five hundred sixty thousand, two hundred eighty-seven".