1663213361 has 4 divisors (see below), whose sum is σ = 1663335924. Its totient is φ = 1663090800.

The previous prime is 1663213327. The next prime is 1663213367. The reversal of 1663213361 is 1633123661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 572166400 + 1091046961 = 23920^2 + 33031^2 .

It is a cyclic number.

It is not a de Polignac number, because 1663213361 - 2¹⁰ = 1663212337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1663213367) 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, 37970 + ... + 69051.

It is an arithmetic number, because the mean of its divisors is an integer number (415833981).

Almost surely, 2^1663213361 is an apocalyptic number.

It is an amenable number.

1663213361 is a deficient number, since it is larger than the sum of its proper divisors (122563).

1663213361 is a wasteful number, since it uses less digits than its factorization.

1663213361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122562.

The product of its digits is 11664, while the sum is 32.

The square root of 1663213361 is about 40782.5129314024. The cubic root of 1663213361 is about 1184.8116659633.

The spelling of 1663213361 in words is "one billion, six hundred sixty-three million, two hundred thirteen thousand, three hundred sixty-one".