21001223112 has 32 divisors (see below), whose sum is σ = 52506624480. Its totient is φ = 6999932160.

The previous prime is 21001223083. The next prime is 21001223137. The reversal of 21001223112 is 21132210012.

It is a junction number, because it is equal to n+sod(n) for n = 21001223091 and 21001223100.

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, 627687 + ... + 660297.

It is an arithmetic number, because the mean of its divisors is an integer number (1640832015).

Almost surely, 2^21001223112 is an apocalyptic number.

It is an amenable number.

21001223112 is an abundant number, since it is smaller than the sum of its proper divisors (31505401368).

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

21001223112 is a wasteful number, since it uses less digits than its factorization.

21001223112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59453 (or 59449 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21001223112 its reverse (21132210012), we get a palindrome (42133433124).

The spelling of 21001223112 in words is "twenty-one billion, one million, two hundred twenty-three thousand, one hundred twelve".