21144410011 has 4 divisors (see below), whose sum is σ = 21147494224. Its totient is φ = 21141325800.

The previous prime is 21144409999. The next prime is 21144410039. The reversal of 21144410011 is 11001444112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21144410011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21144410611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1531800 + ... + 1545541.

It is an arithmetic number, because the mean of its divisors is an integer number (5286873556).

Almost surely, 2^21144410011 is an apocalyptic number.

21144410011 is a deficient number, since it is larger than the sum of its proper divisors (3084213).

21144410011 is an equidigital number, since it uses as much as digits as its factorization.

21144410011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3084212.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21144410011 its reverse (11001444112), we get a palindrome (32145854123).

The spelling of 21144410011 in words is "twenty-one billion, one hundred forty-four million, four hundred ten thousand, eleven".