1665166387579 has 2 divisors, whose sum is σ = 1665166387580. Its totient is φ = 1665166387578.

The previous prime is 1665166387517. The next prime is 1665166387589. The reversal of 1665166387579 is 9757836615661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1665166387579 - 2¹⁵ = 1665166354811 is a prime.

It is not a weakly prime, because it can be changed into another prime (1665166387589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832583193789 + 832583193790.

It is an arithmetic number, because the mean of its divisors is an integer number (832583193790).

Almost surely, 2^{1665166387579} is an apocalyptic number.

1665166387579 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665166387579 is an equidigital number, since it uses as much as digits as its factorization.

1665166387579 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 342921600, while the sum is 70.

The spelling of 1665166387579 in words is "one trillion, six hundred sixty-five billion, one hundred sixty-six million, three hundred eighty-seven thousand, five hundred seventy-nine".