166081579949 has 4 divisors (see below), whose sum is σ = 166083837660. Its totient is φ = 166079322240.

The previous prime is 166081579907. The next prime is 166081579973. The reversal of 166081579949 is 949975180661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 151404257449 + 14677322500 = 389107^2 + 121150^2 .

It is a cyclic number.

It is not a de Polignac number, because 166081579949 - 2¹² = 166081575853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166081579249) 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 in 3 ways as a sum of consecutive naturals, for example, 1014662 + ... + 1166919.

It is an arithmetic number, because the mean of its divisors is an integer number (41520959415).

Almost surely, 2^166081579949 is an apocalyptic number.

It is an amenable number.

166081579949 is a deficient number, since it is larger than the sum of its proper divisors (2257711).

166081579949 is an equidigital number, since it uses as much as digits as its factorization.

166081579949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2257710.

The product of its (nonzero) digits is 29393280, while the sum is 65.

The spelling of 166081579949 in words is "one hundred sixty-six billion, eighty-one million, five hundred seventy-nine thousand, nine hundred forty-nine".