166681818630 has 224 divisors, whose sum is σ = 465031977120. Its totient is φ = 42972042240.

The previous prime is 166681818601. The next prime is 166681818659. The reversal of 166681818630 is 36818186661.

It is an interprime number because it is at equal distance from previous prime (166681818601) and next prime (166681818659).

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 111 ways as a sum of consecutive naturals, for example, 26233534 + ... + 26239886.

Almost surely, 2^166681818630 is an apocalyptic number.

166681818630 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 166681818630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232515988560).

166681818630 is an abundant number, since it is smaller than the sum of its proper divisors (298350158490).

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

166681818630 is an equidigital number, since it uses as much as digits as its factorization.

166681818630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6498 (or 6483 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 54.

The spelling of 166681818630 in words is "one hundred sixty-six billion, six hundred eighty-one million, eight hundred eighteen thousand, six hundred thirty".