21121121113 has 16 divisors (see below), whose sum is σ = 22498819200. Its totient is φ = 19758663936.

The previous prime is 21121121101. The next prime is 21121121233. The reversal of 21121121113 is 31112112112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21121121113 - 2²⁵ = 21087566681 is a prime.

It is a super-2 number, since 2×21121121113² (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 (21121124113) 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, 4101006 + ... + 4106152.

It is an arithmetic number, because the mean of its divisors is an integer number (1406176200).

Almost surely, 2^21121121113 is an apocalyptic number.

It is an amenable number.

21121121113 is a deficient number, since it is larger than the sum of its proper divisors (1377698087).

21121121113 is a wasteful number, since it uses less digits than its factorization.

21121121113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6576.

The product of its digits is 24, while the sum is 16.

Adding to 21121121113 its reverse (31112112112), we get a palindrome (52233233225).

Subtracting 21121121113 from its reverse (31112112112), we obtain a palindrome (9990990999).

It can be divided in two parts, 211211 and 21113, that added together give a square (232324 = 482²).

The spelling of 21121121113 in words is "twenty-one billion, one hundred twenty-one million, one hundred twenty-one thousand, one hundred thirteen".