72730161 has 36 divisors (see below), whose sum is σ = 123741072. Its totient is φ = 41038704.

The previous prime is 72730139. The next prime is 72730181. The reversal of 72730161 is 16103727.

It is not a de Polignac number, because 72730161 - 2⁷ = 72730033 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72730181) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 35610 + ... + 37596.

It is an arithmetic number, because the mean of its divisors is an integer number (3437252).

Almost surely, 2^72730161 is an apocalyptic number.

It is an amenable number.

72730161 is a deficient number, since it is larger than the sum of its proper divisors (51010911).

72730161 is a wasteful number, since it uses less digits than its factorization.

72730161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2090 (or 2080 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 72730161 is about 8528.1979925422. The cubic root of 72730161 is about 417.4183300874.

Adding to 72730161 its reverse (16103727), we get a palindrome (88833888).

The spelling of 72730161 in words is "seventy-two million, seven hundred thirty thousand, one hundred sixty-one".