166420610066523 has 4 divisors (see below), whose sum is σ = 221894146755368. Its totient is φ = 110947073377680.

The previous prime is 166420610066471. The next prime is 166420610066537. The reversal of 166420610066523 is 325660016024661.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 166420610066523 - 2¹⁷ = 166420609935451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166420610066723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27736768344418 + ... + 27736768344423.

It is an arithmetic number, because the mean of its divisors is an integer number (55473536688842).

Almost surely, 2^{166420610066523} is an apocalyptic number.

166420610066523 is a deficient number, since it is larger than the sum of its proper divisors (55473536688845).

166420610066523 is an equidigital number, since it uses as much as digits as its factorization.

166420610066523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55473536688844.

The product of its (nonzero) digits is 1866240, while the sum is 48.

The spelling of 166420610066523 in words is "one hundred sixty-six trillion, four hundred twenty billion, six hundred ten million, sixty-six thousand, five hundred twenty-three".