21012112012 has 12 divisors (see below), whose sum is σ = 36774460800. Its totient is φ = 10505123216.

The previous prime is 21012111983. The next prime is 21012112021. The reversal of 21012112012 is 21021121012.

It is a junction number, because it is equal to n+sod(n) for n = 21012111983 and 21012112001.

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, 181228 + ... + 273619.

It is an arithmetic number, because the mean of its divisors is an integer number (3064538400).

Almost surely, 2^21012112012 is an apocalyptic number.

It is an amenable number.

21012112012 is a deficient number, since it is larger than the sum of its proper divisors (15762348788).

21012112012 is a wasteful number, since it uses less digits than its factorization.

21012112012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466400 (or 466398 counting only the distinct ones).

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

Adding to 21012112012 its reverse (21021121012), we get a palindrome (42033233024).

The spelling of 21012112012 in words is "twenty-one billion, twelve million, one hundred twelve thousand, twelve".