2130165561 has 4 divisors (see below), whose sum is σ = 2840220752. Its totient is φ = 1420110372.

The previous prime is 2130165553. The next prime is 2130165571. The reversal of 2130165561 is 1655610312.

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 not a de Polignac number, because 2130165561 - 2³ = 2130165553 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2130165551) 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, 355027591 + ... + 355027596.

It is an arithmetic number, because the mean of its divisors is an integer number (710055188).

Almost surely, 2^2130165561 is an apocalyptic number.

It is an amenable number.

2130165561 is a deficient number, since it is larger than the sum of its proper divisors (710055191).

2130165561 is an equidigital number, since it uses as much as digits as its factorization.

2130165561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 710055190.

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 2130165561 is about 46153.7166542414. The cubic root of 2130165561 is about 1286.6816866336.

Adding to 2130165561 its reverse (1655610312), we get a palindrome (3785775873).

The spelling of 2130165561 in words is "two billion, one hundred thirty million, one hundred sixty-five thousand, five hundred sixty-one".