172220072171 has 4 divisors (see below), whose sum is σ = 196822939632. Its totient is φ = 147617204712.

The previous prime is 172220072153. The next prime is 172220072173. The reversal of 172220072171 is 171270022271.

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

It is a cyclic number.

It is not a de Polignac number, because 172220072171 - 2¹⁸ = 172219810027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172220072173) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 12301433720 + ... + 12301433733.

It is an arithmetic number, because the mean of its divisors is an integer number (49205734908).

Almost surely, 2^172220072171 is an apocalyptic number.

172220072171 is a deficient number, since it is larger than the sum of its proper divisors (24602867461).

172220072171 is an equidigital number, since it uses as much as digits as its factorization.

172220072171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24602867460.

The product of its (nonzero) digits is 5488, while the sum is 32.

The spelling of 172220072171 in words is "one hundred seventy-two billion, two hundred twenty million, seventy-two thousand, one hundred seventy-one".