21011120201209 has 4 divisors (see below), whose sum is σ = 21022595418880. Its totient is φ = 20999644983540.

The previous prime is 21011120201189. The next prime is 21011120201317. The reversal of 21011120201209 is 90210202111012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21011120201209 - 2¹⁷ = 21011120070137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21011120201209.

It is not an unprimeable number, because it can be changed into a prime (21011120201809) 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, 5737606089 + ... + 5737609750.

It is an arithmetic number, because the mean of its divisors is an integer number (5255648854720).

Almost surely, 2^{21011120201209} is an apocalyptic number.

It is an amenable number.

21011120201209 is a deficient number, since it is larger than the sum of its proper divisors (11475217671).

21011120201209 is a wasteful number, since it uses less digits than its factorization.

21011120201209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11475217670.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 21011120201209 in words is "twenty-one trillion, eleven billion, one hundred twenty million, two hundred one thousand, two hundred nine".