21212013311 has 4 divisors (see below), whose sum is σ = 21213283824. Its totient is φ = 21210742800.

The previous prime is 21212013299. The next prime is 21212013323. The reversal of 21212013311 is 11331021212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21212013299) and next prime (21212013323).

It is a cyclic number.

It is not a de Polignac number, because 21212013311 - 2¹⁰ = 21212012287 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 21212013311.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212010311) 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, 609875 + ... + 643716.

It is an arithmetic number, because the mean of its divisors is an integer number (5303320956).

Almost surely, 2^21212013311 is an apocalyptic number.

21212013311 is a deficient number, since it is larger than the sum of its proper divisors (1270513).

21212013311 is a wasteful number, since it uses less digits than its factorization.

21212013311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1270512.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21212013311 its reverse (11331021212), we get a palindrome (32543034523).

The spelling of 21212013311 in words is "twenty-one billion, two hundred twelve million, thirteen thousand, three hundred eleven".