172766661 has 16 divisors (see below), whose sum is σ = 238327488. Its totient is φ = 111248000.

The previous prime is 172766641. The next prime is 172766687. The reversal of 172766661 is 166667271.

It is a cyclic number.

It is not a de Polignac number, because 172766661 - 2¹⁵ = 172733893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172766641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5470 + ... + 19376.

It is an arithmetic number, because the mean of its divisors is an integer number (14895468).

Almost surely, 2^172766661 is an apocalyptic number.

It is an amenable number.

172766661 is a deficient number, since it is larger than the sum of its proper divisors (65560827).

172766661 is a wasteful number, since it uses less digits than its factorization.

172766661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14052.

The product of its digits is 127008, while the sum is 42.

The square root of 172766661 is about 13144.0732271241. The cubic root of 172766661 is about 556.9548369124.

The spelling of 172766661 in words is "one hundred seventy-two million, seven hundred sixty-six thousand, six hundred sixty-one".