72172001 has 4 divisors (see below), whose sum is σ = 78733104. Its totient is φ = 65610900.

The previous prime is 72171991. The next prime is 72172003. The reversal of 72172001 is 10027127.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72172001 - 2¹⁰ = 72170977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72172003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3280535 + ... + 3280556.

It is an arithmetic number, because the mean of its divisors is an integer number (19683276).

Almost surely, 2^72172001 is an apocalyptic number.

It is an amenable number.

72172001 is a deficient number, since it is larger than the sum of its proper divisors (6561103).

72172001 is a wasteful number, since it uses less digits than its factorization.

72172001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6561102.

The product of its (nonzero) digits is 196, while the sum is 20.

The square root of 72172001 is about 8495.4105845450. The cubic root of 72172001 is about 416.3477757006.

Adding to 72172001 its reverse (10027127), we get a palindrome (82199128).

The spelling of 72172001 in words is "seventy-two million, one hundred seventy-two thousand, one".