21144319999 has 4 divisors (see below), whose sum is σ = 23066530920. Its totient is φ = 19222109080.

The previous prime is 21144319997. The next prime is 21144320011. The reversal of 21144319999 is 99991344112.

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 21144319999 - 2¹ = 21144319997 is a prime.

It is a super-2 number, since 2×21144319999² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144319997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 961105444 + ... + 961105465.

It is an arithmetic number, because the mean of its divisors is an integer number (5766632730).

Almost surely, 2^21144319999 is an apocalyptic number.

21144319999 is a deficient number, since it is larger than the sum of its proper divisors (1922210921).

21144319999 is a wasteful number, since it uses less digits than its factorization.

21144319999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1922210920.

The product of its digits is 629856, while the sum is 52.

It can be divided in two parts, 21144 and 319999, that added together give a palindrome (341143).

The spelling of 21144319999 in words is "twenty-one billion, one hundred forty-four million, three hundred nineteen thousand, nine hundred ninety-nine".