2209563981 has 8 divisors (see below), whose sum is σ = 3273428160. Its totient is φ = 1473042636.

The previous prime is 2209563973. The next prime is 2209563991. The reversal of 2209563981 is 1893659022.

2209563981 is a `hidden beast` number, since 2 + 2 + 0 + 9 + 5 + 639 + 8 + 1 = 666.

It is not a de Polignac number, because 2209563981 - 2³ = 2209563973 is a prime.

It is a super-2 number, since 2×2209563981² = 9764345972265136722, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2209563991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40917825 + ... + 40917878.

It is an arithmetic number, because the mean of its divisors is an integer number (409178520).

Almost surely, 2^2209563981 is an apocalyptic number.

It is an amenable number.

2209563981 is a deficient number, since it is larger than the sum of its proper divisors (1063864179).

2209563981 is an equidigital number, since it uses as much as digits as its factorization.

2209563981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81835712 (or 81835706 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The square root of 2209563981 is about 47005.9994149683. Note that the first 3 decimals coincide. The cubic root of 2209563981 is about 1302.4733938713.

The spelling of 2209563981 in words is "two billion, two hundred nine million, five hundred sixty-three thousand, nine hundred eighty-one".