21121121212 has 12 divisors (see below), whose sum is σ = 37327922856. Its totient is φ = 10456000400.

The previous prime is 21121121101. The next prime is 21121121233. The reversal of 21121121212 is 21212112112.

It is a super-2 number, since 2×21121121212² (a number of 21 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26139598 + ... + 26140405.

It is an arithmetic number, because the mean of its divisors is an integer number (3110660238).

Almost surely, 2^21121121212 is an apocalyptic number.

It is an amenable number.

21121121212 is a deficient number, since it is larger than the sum of its proper divisors (16206801644).

21121121212 is a wasteful number, since it uses less digits than its factorization.

21121121212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52280108 (or 52280106 counting only the distinct ones).

The product of its digits is 32, while the sum is 16.

Adding to 21121121212 its reverse (21212112112), we get a palindrome (42333233324).

The spelling of 21121121212 in words is "twenty-one billion, one hundred twenty-one million, one hundred twenty-one thousand, two hundred twelve".