172370660720666 has 4 divisors (see below), whose sum is σ = 258555991081002. Its totient is φ = 86185330360332.

The previous prime is 172370660720653. The next prime is 172370660720669. The reversal of 172370660720666 is 666027066073271.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 87205060873225 + 85165599847441 = 9338365^2 + 9228521^2 .

It is not an unprimeable number, because it can be changed into a prime (172370660720669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43092665180165 + ... + 43092665180168.

Almost surely, 2^{172370660720666} is an apocalyptic number.

172370660720666 is a deficient number, since it is larger than the sum of its proper divisors (86185330360336).

172370660720666 is an equidigital number, since it uses as much as digits as its factorization.

172370660720666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86185330360335.

The product of its (nonzero) digits is 32006016, while the sum is 59.

The spelling of 172370660720666 in words is "one hundred seventy-two trillion, three hundred seventy billion, six hundred sixty million, seven hundred twenty thousand, six hundred sixty-six".