2164721263 has 4 divisors (see below), whose sum is σ = 2167352368. Its totient is φ = 2162090160.

The previous prime is 2164721261. The next prime is 2164721303. The reversal of 2164721263 is 3621274612.

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

It is a cyclic number.

It is not a de Polignac number, because 2164721263 - 2¹ = 2164721261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2164721261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1314318 + ... + 1315963.

It is an arithmetic number, because the mean of its divisors is an integer number (541838092).

Almost surely, 2^2164721263 is an apocalyptic number.

2164721263 is a deficient number, since it is larger than the sum of its proper divisors (2631105).

2164721263 is an equidigital number, since it uses as much as digits as its factorization.

2164721263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2631104.

The product of its digits is 24192, while the sum is 34.

The square root of 2164721263 is about 46526.5651321909. The cubic root of 2164721263 is about 1293.6019483534.

Adding to 2164721263 its reverse (3621274612), we get a palindrome (5785995875).

The spelling of 2164721263 in words is "two billion, one hundred sixty-four million, seven hundred twenty-one thousand, two hundred sixty-three".