166883781919 has 4 divisors (see below), whose sum is σ = 167331191896. Its totient is φ = 166436371944.

The previous prime is 166883781907. The next prime is 166883781923. The reversal of 166883781919 is 919187388661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 919187388661 = 1733 ⋅530402417.

It is a cyclic number.

It is not a de Polignac number, because 166883781919 - 2²⁵ = 166850227487 is a prime.

It is a super-3 number, since 3×166883781919³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166883281919) 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, 223704429 + ... + 223705174.

It is an arithmetic number, because the mean of its divisors is an integer number (41832797974).

Almost surely, 2^166883781919 is an apocalyptic number.

166883781919 is a deficient number, since it is larger than the sum of its proper divisors (447409977).

166883781919 is an equidigital number, since it uses as much as digits as its factorization.

166883781919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447409976.

The product of its digits is 31352832, while the sum is 67.

The spelling of 166883781919 in words is "one hundred sixty-six billion, eight hundred eighty-three million, seven hundred eighty-one thousand, nine hundred nineteen".