720165161 has 12 divisors (see below), whose sum is σ = 753080832. Its totient is φ = 688367736.

The previous prime is 720165139. The next prime is 720165163. The reversal of 720165161 is 161561027.

It is not a de Polignac number, because 720165161 - 2⁶ = 720165097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (720165163) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 82760 + ... + 91046.

It is an arithmetic number, because the mean of its divisors is an integer number (62756736).

Almost surely, 2^720165161 is an apocalyptic number.

It is an amenable number.

720165161 is a deficient number, since it is larger than the sum of its proper divisors (32915671).

720165161 is an equidigital number, since it uses as much as digits as its factorization.

720165161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8420 (or 8377 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 720165161 is about 26835.8931470521. The cubic root of 720165161 is about 896.3494767838.

It can be divided in two parts, 72016 and 5161, that added together give a palindrome (77177).

The spelling of 720165161 in words is "seven hundred twenty million, one hundred sixty-five thousand, one hundred sixty-one".