21002121112 has 32 divisors (see below), whose sum is σ = 45264708000. Its totient is φ = 8948876544.

The previous prime is 21002121073. The next prime is 21002121157. The reversal of 21002121112 is 21112120012.

It is a super-2 number, since 2×21002121112² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21002121092 and 21002121101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1074237 + ... + 1093612.

It is an arithmetic number, because the mean of its divisors is an integer number (1414522125).

Almost surely, 2^21002121112 is an apocalyptic number.

It is an amenable number.

21002121112 is an abundant number, since it is smaller than the sum of its proper divisors (24262586888).

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

21002121112 is a wasteful number, since it uses less digits than its factorization.

21002121112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2168035 (or 2168031 counting only the distinct ones).

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

Adding to 21002121112 its reverse (21112120012), we get a palindrome (42114241124).

It can be divided in two parts, 2100 and 2121112, that added together give a palindrome (2123212).

The spelling of 21002121112 in words is "twenty-one billion, two million, one hundred twenty-one thousand, one hundred twelve".