2205656561 has 4 divisors (see below), whose sum is σ = 2252585472. Its totient is φ = 2158727652.

The previous prime is 2205656539. The next prime is 2205656581. The reversal of 2205656561 is 1656565022.

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 2205656561 - 2¹⁸ = 2205394417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2205656581) 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, 23464385 + ... + 23464478.

It is an arithmetic number, because the mean of its divisors is an integer number (563146368).

Almost surely, 2^2205656561 is an apocalyptic number.

It is an amenable number.

2205656561 is a deficient number, since it is larger than the sum of its proper divisors (46928911).

2205656561 is an equidigital number, since it uses as much as digits as its factorization.

2205656561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46928910.

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 2205656561 is about 46964.4180311009. The cubic root of 2205656561 is about 1301.7051708820.

The spelling of 2205656561 in words is "two billion, two hundred five million, six hundred fifty-six thousand, five hundred sixty-one".