21210214221612 has 144 divisors (see below), whose sum is σ = 58557806798400. Its totient is φ = 6433678540800.

The previous prime is 21210214221583. The next prime is 21210214221617. The reversal of 21210214221612 is 21612241201212.

21210214221612 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 0 + 2 + 1 + 42 + 2 + 1 + 612 = 666.

It is not an unprimeable number, because it can be changed into a prime (21210214221617) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 435960264 + ... + 436008912.

It is an arithmetic number, because the mean of its divisors is an integer number (406651436100).

Almost surely, 2^{21210214221612} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21210214221612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29278903399200).

21210214221612 is an abundant number, since it is smaller than the sum of its proper divisors (37347592576788).

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

21210214221612 is a wasteful number, since it uses less digits than its factorization.

21210214221612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61864 (or 61859 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

Adding to 21210214221612 its reverse (21612241201212), we get a palindrome (42822455422824).

The spelling of 21210214221612 in words is "twenty-one trillion, two hundred ten billion, two hundred fourteen million, two hundred twenty-one thousand, six hundred twelve".