21224657916 has 162 divisors, whose sum is σ = 68600772240. Its totient is φ = 5512842720.

The previous prime is 21224657891. The next prime is 21224657963. The reversal of 21224657916 is 61975642212.

21224657916 is a `hidden beast` number, since 2 + 1 + 22 + 46 + 579 + 16 = 666.

It is a super-2 number, since 2×21224657916² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 53 ways as a sum of consecutive naturals, for example, 163725 + ... + 263163.

Almost surely, 2^21224657916 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 21224657916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34300386120).

21224657916 is an abundant number, since it is smaller than the sum of its proper divisors (47376114324).

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

21224657916 is a wasteful number, since it uses less digits than its factorization.

21224657916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99485 (or 99462 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The spelling of 21224657916 in words is "twenty-one billion, two hundred twenty-four million, six hundred fifty-seven thousand, nine hundred sixteen".