166649543406 has 96 divisors (see below), whose sum is σ = 404891405568. Its totient is φ = 49262526720.

The previous prime is 166649543363. The next prime is 166649543407. The reversal of 166649543406 is 604345946661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166649543407) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 294841 + ... + 648251.

It is an arithmetic number, because the mean of its divisors is an integer number (4217618808).

Almost surely, 2^166649543406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166649543406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (202445702784).

166649543406 is an abundant number, since it is smaller than the sum of its proper divisors (238241862162).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166649543406 is a wasteful number, since it uses less digits than its factorization.

166649543406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353526 (or 353523 counting only the distinct ones).

The product of its (nonzero) digits is 11197440, while the sum is 54.

The spelling of 166649543406 in words is "one hundred sixty-six billion, six hundred forty-nine million, five hundred forty-three thousand, four hundred six".