2127122561 has 4 divisors (see below), whose sum is σ = 2239076400. Its totient is φ = 2015168724.

The previous prime is 2127122551. The next prime is 2127122597. The reversal of 2127122561 is 1652217212.

It is a happy number.

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 2127122561 - 2³⁰ = 1053380737 is a prime.

It is a super-3 number, since 3×2127122561³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2127122531) 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, 55976891 + ... + 55976928.

It is an arithmetic number, because the mean of its divisors is an integer number (559769100).

Almost surely, 2^2127122561 is an apocalyptic number.

It is an amenable number.

2127122561 is a deficient number, since it is larger than the sum of its proper divisors (111953839).

2127122561 is a wasteful number, since it uses less digits than its factorization.

2127122561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111953838.

The product of its digits is 3360, while the sum is 29.

The square root of 2127122561 is about 46120.7389468122. The cubic root of 2127122561 is about 1286.0687079476.

Adding to 2127122561 its reverse (1652217212), we get a palindrome (3779339773).

The spelling of 2127122561 in words is "two billion, one hundred twenty-seven million, one hundred twenty-two thousand, five hundred sixty-one".