30720726161 has 4 divisors (see below), whose sum is σ = 30721324272. Its totient is φ = 30720128052.

The previous prime is 30720726151. The next prime is 30720726187. The reversal of 30720726161 is 16162702703.

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 30720726161 - 2²⁶ = 30653617297 is a prime.

It is a super-3 number, since 3×30720726161³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30720726151) 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, 213935 + ... + 327428.

It is an arithmetic number, because the mean of its divisors is an integer number (7680331068).

Almost surely, 2^30720726161 is an apocalyptic number.

It is an amenable number.

30720726161 is a deficient number, since it is larger than the sum of its proper divisors (598111).

30720726161 is an equidigital number, since it uses as much as digits as its factorization.

30720726161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598110.

The product of its (nonzero) digits is 21168, while the sum is 35.

The spelling of 30720726161 in words is "thirty billion, seven hundred twenty million, seven hundred twenty-six thousand, one hundred sixty-one".