166538446336091 has 2 divisors, whose sum is σ = 166538446336092. Its totient is φ = 166538446336090.

The previous prime is 166538446336061. The next prime is 166538446336103. The reversal of 166538446336091 is 190633644835661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166538446336091 - 2⁴² = 162140399824987 is a prime.

It is not a weakly prime, because it can be changed into another prime (166538446336051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83269223168045 + 83269223168046.

It is an arithmetic number, because the mean of its divisors is an integer number (83269223168046).

Almost surely, 2^{166538446336091} is an apocalyptic number.

166538446336091 is a deficient number, since it is larger than the sum of its proper divisors (1).

166538446336091 is an equidigital number, since it uses as much as digits as its factorization.

166538446336091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 201553920, while the sum is 65.

The spelling of 166538446336091 in words is "one hundred sixty-six trillion, five hundred thirty-eight billion, four hundred forty-six million, three hundred thirty-six thousand, ninety-one".