21116404201 has 4 divisors (see below), whose sum is σ = 21844556100. Its totient is φ = 20388252304.

The previous prime is 21116404187. The next prime is 21116404207. The reversal of 21116404201 is 10240461112.

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 12214670400 + 8901733801 = 110520^2 + 94349^2 .

It is a cyclic number.

It is not a de Polignac number, because 21116404201 - 2⁹ = 21116403689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21116404207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364075906 + ... + 364075963.

It is an arithmetic number, because the mean of its divisors is an integer number (5461139025).

Almost surely, 2^21116404201 is an apocalyptic number.

It is an amenable number.

21116404201 is a deficient number, since it is larger than the sum of its proper divisors (728151899).

21116404201 is an equidigital number, since it uses as much as digits as its factorization.

21116404201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728151898.

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 21116404201 its reverse (10240461112), we get a palindrome (31356865313).

The spelling of 21116404201 in words is "twenty-one billion, one hundred sixteen million, four hundred four thousand, two hundred one".