21011220112 has 10 divisors (see below), whose sum is σ = 40709238998. Its totient is φ = 10505610048.

The previous prime is 21011220089. The next prime is 21011220121. The reversal of 21011220112 is 21102211012.

It can be written as a sum of positive squares in only one way, i.e., 12491191696 + 8520028416 = 111764^2 + 92304^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21011220092 and 21011220101.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656600613 + ... + 656600644.

Almost surely, 2^21011220112 is an apocalyptic number.

It is an amenable number.

21011220112 is a deficient number, since it is larger than the sum of its proper divisors (19698018886).

21011220112 is a wasteful number, since it uses less digits than its factorization.

21011220112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1313201265 (or 1313201259 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21011220112 its reverse (21102211012), we get a palindrome (42113431124).

The spelling of 21011220112 in words is "twenty-one billion, eleven million, two hundred twenty thousand, one hundred twelve".