21212111120 has 40 divisors (see below), whose sum is σ = 49325139864. Its totient is φ = 8483643392.

The previous prime is 21212111101. The next prime is 21212111143. The reversal of 21212111120 is 2111121212.

It can be written as a sum of positive squares in 4 ways, for example, as 4596736 + 21207514384 = 2144^2 + 145628^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 21212111095 and 21212111104.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 740912 + ... + 769008.

Almost surely, 2^21212111120 is an apocalyptic number.

21212111120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212111120 is an abundant number, since it is smaller than the sum of its proper divisors (28113028744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21212111120 is a wasteful number, since it uses less digits than its factorization.

21212111120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37547 (or 37541 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21212111120 its reverse (2111121212), we get a palindrome (23323232332).

The spelling of 21212111120 in words is "twenty-one billion, two hundred twelve million, one hundred eleven thousand, one hundred twenty".