66665580283787 has 2 divisors, whose sum is σ = 66665580283788. Its totient is φ = 66665580283786.

The previous prime is 66665580283781. The next prime is 66665580283891. The reversal of 66665580283787 is 78738208556666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66665580283787 - 2¹² = 66665580279691 is a prime.

It is a super-2 number, since 2×66665580283787² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66665580283781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33332790141893 + 33332790141894.

It is an arithmetic number, because the mean of its divisors is an integer number (33332790141894).

Almost surely, 2^{66665580283787} is an apocalyptic number.

66665580283787 is a deficient number, since it is larger than the sum of its proper divisors (1).

66665580283787 is an equidigital number, since it uses as much as digits as its factorization.

66665580283787 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4877107200, while the sum is 77.

The spelling of 66665580283787 in words is "sixty-six trillion, six hundred sixty-five billion, five hundred eighty million, two hundred eighty-three thousand, seven hundred eighty-seven".