21211201232311 has 4 divisors (see below), whose sum is σ = 21213753424624. Its totient is φ = 21208649040000.

The previous prime is 21211201232293. The next prime is 21211201232317. The reversal of 21211201232311 is 11323210211212.

It is a happy number.

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 21211201232311 - 2¹⁹ = 21211200708023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211201232317) 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, 1276083690 + ... + 1276100311.

It is an arithmetic number, because the mean of its divisors is an integer number (5303438356156).

Almost surely, 2^{21211201232311} is an apocalyptic number.

21211201232311 is a deficient number, since it is larger than the sum of its proper divisors (2552192313).

21211201232311 is an equidigital number, since it uses as much as digits as its factorization.

21211201232311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2552192312.

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 21211201232311 its reverse (11323210211212), we get a palindrome (32534411443523).

The spelling of 21211201232311 in words is "twenty-one trillion, two hundred eleven billion, two hundred one million, two hundred thirty-two thousand, three hundred eleven".