21011221022112 has 36 divisors (see below), whose sum is σ = 59750659782450. Its totient is φ = 7003740340608.

The previous prime is 21011221022111. The next prime is 21011221022149. The reversal of 21011221022112 is 21122012211012.

21011221022112 is a `hidden beast` number, since 210 + 1 + 1 + 221 + 0 + 221 + 12 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20917121778576 + 94099243536 = 4573524^2 + 306756^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21011221022111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36477813987 + ... + 36477814562.

Almost surely, 2^{21011221022112} is an apocalyptic number.

It is an amenable number.

21011221022112 is an abundant number, since it is smaller than the sum of its proper divisors (38739438760338).

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

21011221022112 is a wasteful number, since it uses less digits than its factorization.

21011221022112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72955628565 (or 72955628554 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21011221022112 its reverse (21122012211012), we get a palindrome (42133233233124).

The spelling of 21011221022112 in words is "twenty-one trillion, eleven billion, two hundred twenty-one million, twenty-two thousand, one hundred twelve".