1666640014643 has 2 divisors, whose sum is σ = 1666640014644. Its totient is φ = 1666640014642.

The previous prime is 1666640014591. The next prime is 1666640014649. The reversal of 1666640014643 is 3464100466661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1666640014643 - 2³² = 1662345047347 is a prime.

It is not a weakly prime, because it can be changed into another prime (1666640014649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833320007321 + 833320007322.

It is an arithmetic number, because the mean of its divisors is an integer number (833320007322).

Almost surely, 2^{1666640014643} is an apocalyptic number.

1666640014643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666640014643 is an equidigital number, since it uses as much as digits as its factorization.

1666640014643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 47.

The spelling of 1666640014643 in words is "one trillion, six hundred sixty-six billion, six hundred forty million, fourteen thousand, six hundred forty-three".