166666542 has 48 divisors (see below), whose sum is σ = 390044160. Its totient is φ = 47338032.

The previous prime is 166666481. The next prime is 166666547. The reversal of 166666542 is 245666661.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 166666494 and 166666503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166666547) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 51043 + ... + 54209.

It is an arithmetic number, because the mean of its divisors is an integer number (8125920).

Almost surely, 2^166666542 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166666542, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (195022080).

166666542 is an abundant number, since it is smaller than the sum of its proper divisors (223377618).

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

166666542 is a wasteful number, since it uses less digits than its factorization.

166666542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3365 (or 3358 counting only the distinct ones).

The product of its digits is 311040, while the sum is 42.

The square root of 166666542 is about 12909.9396590379. The cubic root of 166666542 is about 550.3210709356.

The spelling of 166666542 in words is "one hundred sixty-six million, six hundred sixty-six thousand, five hundred forty-two".