21214445616 has 600 divisors, whose sum is σ = 77297847264. Its totient is φ = 5499187200.

The previous prime is 21214445587. The next prime is 21214445621. The reversal of 21214445616 is 61654441212.

21214445616 is a `hidden beast` number, since 21 + 2 + 14 + 4 + 4 + 5 + 616 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 154849900 + ... + 154850036.

Almost surely, 2^21214445616 is an apocalyptic number.

21214445616 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21214445616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38648923632).

21214445616 is an abundant number, since it is smaller than the sum of its proper divisors (56083401648).

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

21214445616 is a wasteful number, since it uses less digits than its factorization.

21214445616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291 (or 263 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

Adding to 21214445616 its reverse (61654441212), we get a palindrome (82868886828).

The spelling of 21214445616 in words is "twenty-one billion, two hundred fourteen million, four hundred forty-five thousand, six hundred sixteen".