2211642561 has 4 divisors (see below), whose sum is σ = 2948856752. Its totient is φ = 1474428372.

The previous prime is 2211642509. The next prime is 2211642569. The reversal of 2211642561 is 1652461122.

2211642561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2211642561 - 2³⁰ = 1137900737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2211642569) 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, 368607091 + ... + 368607096.

It is an arithmetic number, because the mean of its divisors is an integer number (737214188).

Almost surely, 2^2211642561 is an apocalyptic number.

It is an amenable number.

2211642561 is a deficient number, since it is larger than the sum of its proper divisors (737214191).

2211642561 is an equidigital number, since it uses as much as digits as its factorization.

2211642561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 737214190.

The product of its digits is 5760, while the sum is 30.

The square root of 2211642561 is about 47028.1039485965. The cubic root of 2211642561 is about 1302.8816865900.

The spelling of 2211642561 in words is "two billion, two hundred eleven million, six hundred forty-two thousand, five hundred sixty-one".