166600638 has 80 divisors (see below), whose sum is σ = 396465696. Its totient is φ = 52176960.

The previous prime is 166600633. The next prime is 166600639. The reversal of 166600638 is 836006661.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166600633) 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 39 ways as a sum of consecutive naturals, for example, 226920 + ... + 227652.

Almost surely, 2^166600638 is an apocalyptic number.

166600638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 166600638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (198232848).

166600638 is an abundant number, since it is smaller than the sum of its proper divisors (229865058).

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

166600638 is a wasteful number, since it uses less digits than its factorization.

166600638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 831 (or 822 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 166600638 is about 12907.3869547635. The cubic root of 166600638 is about 550.2485245986.

The spelling of 166600638 in words is "one hundred sixty-six million, six hundred thousand, six hundred thirty-eight".