21200091011 has 4 divisors (see below), whose sum is σ = 23127372024. Its totient is φ = 19272810000.

The previous prime is 21200091007. The next prime is 21200091019. The reversal of 21200091011 is 11019000212.

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 21200091011 - 2² = 21200091007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200091019) 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, 963640490 + ... + 963640511.

It is an arithmetic number, because the mean of its divisors is an integer number (5781843006).

Almost surely, 2^21200091011 is an apocalyptic number.

21200091011 is a deficient number, since it is larger than the sum of its proper divisors (1927281013).

21200091011 is a wasteful number, since it uses less digits than its factorization.

21200091011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1927281012.

The product of its (nonzero) digits is 36, while the sum is 17.

Adding to 21200091011 its reverse (11019000212), we get a palindrome (32219091223).

The spelling of 21200091011 in words is "twenty-one billion, two hundred million, ninety-one thousand, eleven".