20111221211 has 8 divisors (see below), whose sum is σ = 20578110000. Its totient is φ = 19648758240.

The previous prime is 20111221199. The next prime is 20111221219. The reversal of 20111221211 is 11212211102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20111221211 - 2⁶ = 20111221147 is a prime.

It is a super-2 number, since 2×20111221211² (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 (20111221219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1097261 + ... + 1115438.

It is an arithmetic number, because the mean of its divisors is an integer number (2572263750).

Almost surely, 2^20111221211 is an apocalyptic number.

20111221211 is a deficient number, since it is larger than the sum of its proper divisors (466888789).

20111221211 is a wasteful number, since it uses less digits than its factorization.

20111221211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2212909.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 20111221211 its reverse (11212211102), we get a palindrome (31323432313).

The spelling of 20111221211 in words is "twenty billion, one hundred eleven million, two hundred twenty-one thousand, two hundred eleven".