21231020211 has 8 divisors (see below), whose sum is σ = 28842140880. Its totient is φ = 13886956512.

The previous prime is 21231020191. The next prime is 21231020219. The reversal of 21231020211 is 11202013212.

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

It is not a de Polignac number, because 21231020211 - 2¹⁷ = 21230889139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21231020219) 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, 66764056 + ... + 66764373.

It is an arithmetic number, because the mean of its divisors is an integer number (3605267610).

Almost surely, 2^21231020211 is an apocalyptic number.

21231020211 is a deficient number, since it is larger than the sum of its proper divisors (7611120669).

21231020211 is a wasteful number, since it uses less digits than its factorization.

21231020211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133528485.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21231020211 its reverse (11202013212), we get a palindrome (32433033423).

The spelling of 21231020211 in words is "twenty-one billion, two hundred thirty-one million, twenty thousand, two hundred eleven".