166989101449 has 3 divisors (see below), whose sum is σ = 166989510093. Its totient is φ = 166988692806.

The previous prime is 166989101431. The next prime is 166989101497. The reversal of 166989101449 is 944101989661.

The square root of 166989101449 is 408643.

It is a perfect power (a square), and thus also a powerful number.

166989101449 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 944101989661 = 83 ⋅11374722767.

It is not a de Polignac number, because 166989101449 - 2²⁹ = 166452230537 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166989101393 and 166989101402.

It is not an unprimeable number, because it can be changed into a prime (166989101429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 204322 + ... + 612964.

It is an arithmetic number, because the mean of its divisors is an integer number (55663170031).

Almost surely, 2^166989101449 is an apocalyptic number.

166989101449 is the 408643-rd square number.

166989101449 is the 204322-nd centered octagonal number.

It is an amenable number.

166989101449 is a deficient number, since it is larger than the sum of its proper divisors (408644).

166989101449 is an frugal number, since it uses more digits than its factorization.

166989101449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 817286 (or 408643 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 58.

The spelling of 166989101449 in words is "one hundred sixty-six billion, nine hundred eighty-nine million, one hundred one thousand, four hundred forty-nine".