21210012112 has 20 divisors (see below), whose sum is σ = 42511447620. Its totient is φ = 10239315968.

The previous prime is 21210012079. The next prime is 21210012169. The reversal of 21210012112 is 21121001212.

It can be written as a sum of positive squares in 2 ways, for example, as 14698167696 + 6511844416 = 121236^2 + 80696^2 .

It is a super-2 number, since 2×21210012112² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21210012092 and 21210012101.

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, 22855153 + ... + 22856080.

It is an arithmetic number, because the mean of its divisors is an integer number (2125572381).

Almost surely, 2^21210012112 is an apocalyptic number.

It is an amenable number.

21210012112 is an abundant number, since it is smaller than the sum of its proper divisors (21301435508).

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

21210012112 is a wasteful number, since it uses less digits than its factorization.

21210012112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45711270 (or 45711264 counting only the distinct ones).

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

Adding to 21210012112 its reverse (21121001212), we get a palindrome (42331013324).

The spelling of 21210012112 in words is "twenty-one billion, two hundred ten million, twelve thousand, one hundred twelve".