173538666 has 128 divisors (see below), whose sum is σ = 471705600. Its totient is φ = 46189440.

The previous prime is 173538653. The next prime is 173538671. The reversal of 173538666 is 666835371.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a zygodrome in base 4.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 524121 + ... + 524451.

It is an arithmetic number, because the mean of its divisors is an integer number (3685200).

Almost surely, 2^173538666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 173538666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235852800).

173538666 is an abundant number, since it is smaller than the sum of its proper divisors (298166934).

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

173538666 is a wasteful number, since it uses less digits than its factorization.

173538666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441 (or 435 counting only the distinct ones).

The product of its digits is 544320, while the sum is 45.

The square root of 173538666 is about 13173.4075318423. The cubic root of 173538666 is about 557.7831855084.

It can be divided in two parts, 1735 and 38666, that added together give a square (40401 = 201²).

The spelling of 173538666 in words is "one hundred seventy-three million, five hundred thirty-eight thousand, six hundred sixty-six".