166669643520 has 720 divisors, whose sum is σ = 639461148480. Its totient is φ = 41341943808.

The previous prime is 166669643501. The next prime is 166669643531. The reversal of 166669643520 is 25346966661.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 88230736 + ... + 88232624.

It is an arithmetic number, because the mean of its divisors is an integer number (888140484).

Almost surely, 2^166669643520 is an apocalyptic number.

166669643520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166669643520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319730574240).

166669643520 is an abundant number, since it is smaller than the sum of its proper divisors (472791504960).

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

166669643520 is a wasteful number, since it uses less digits than its factorization.

166669643520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1982 (or 1959 counting only the distinct ones).

The product of its (nonzero) digits is 8398080, while the sum is 54.

The spelling of 166669643520 in words is "one hundred sixty-six billion, six hundred sixty-nine million, six hundred forty-three thousand, five hundred twenty".