21200244011 has 4 divisors (see below), whose sum is σ = 21200763000. Its totient is φ = 21199725024.

The previous prime is 21200244007. The next prime is 21200244031. The reversal of 21200244011 is 11044200212.

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 21200244011 - 2² = 21200244007 is a prime.

It is a super-2 number, since 2×21200244011² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200244031) 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, 192446 + ... + 281843.

It is an arithmetic number, because the mean of its divisors is an integer number (5300190750).

Almost surely, 2^21200244011 is an apocalyptic number.

21200244011 is a deficient number, since it is larger than the sum of its proper divisors (518989).

21200244011 is an equidigital number, since it uses as much as digits as its factorization.

21200244011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518988.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21200244011 its reverse (11044200212), we get a palindrome (32244444223).

The spelling of 21200244011 in words is "twenty-one billion, two hundred million, two hundred forty-four thousand, eleven".