21213130111 has 16 divisors (see below), whose sum is σ = 22709072736. Its totient is φ = 19745058816.

The previous prime is 21213130093. The next prime is 21213130223. The reversal of 21213130111 is 11103131212.

It is a happy number.

It is not a de Polignac number, because 21213130111 - 2⁷ = 21213129983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223130111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2745025 + ... + 2752741.

It is an arithmetic number, because the mean of its divisors is an integer number (1419317046).

Almost surely, 2^21213130111 is an apocalyptic number.

21213130111 is a deficient number, since it is larger than the sum of its proper divisors (1495942625).

21213130111 is a wasteful number, since it uses less digits than its factorization.

21213130111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9498.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 21213130111 its reverse (11103131212), we get a palindrome (32316261323).

It can be divided in two parts, 212131 and 30111, that added together give a palindrome (242242).

The spelling of 21213130111 in words is "twenty-one billion, two hundred thirteen million, one hundred thirty thousand, one hundred eleven".