660678021332861 has 12 divisors (see below), whose sum is σ = 755678496566112. Its totient is φ = 565832399911896.

The previous prime is 660678021332821. The next prime is 660678021332891. The reversal of 660678021332861 is 168233120876066.

It is a de Polignac number, because none of the positive numbers 2^k-660678021332861 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 660678021332861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660678021332821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21080591 + ... + 42020796.

It is an arithmetic number, because the mean of its divisors is an integer number (62973208047176).

Almost surely, 2^{660678021332861} is an apocalyptic number.

It is an amenable number.

660678021332861 is a deficient number, since it is larger than the sum of its proper divisors (95000475233251).

660678021332861 is an frugal number, since it uses more digits than its factorization.

660678021332861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63103840 (or 63102617 counting only the distinct ones).

The product of its (nonzero) digits is 20901888, while the sum is 59.

The spelling of 660678021332861 in words is "six hundred sixty trillion, six hundred seventy-eight billion, twenty-one million, three hundred thirty-two thousand, eight hundred sixty-one".