9172720 has 20 divisors (see below), whose sum is σ = 21326760. Its totient is φ = 3669056.

The previous prime is 9172693. The next prime is 9172721. The reversal of 9172720 is 272719.

It is a happy number.

9172720 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (20).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9172721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57250 + ... + 57409.

It is an arithmetic number, because the mean of its divisors is an integer number (1066338).

Almost surely, 2^9172720 is an apocalyptic number.

It is an amenable number.

9172720 is an abundant number, since it is smaller than the sum of its proper divisors (12154040).

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

9172720 is a wasteful number, since it uses less digits than its factorization.

9172720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114672 (or 114666 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 28.

The square root of 9172720 is about 3028.6498642134. The cubic root of 9172720 is about 209.3305971036.

The spelling of 9172720 in words is "nine million, one hundred seventy-two thousand, seven hundred twenty".