21225416648 has 36 divisors (see below), whose sum is σ = 42018011595. Its totient is φ = 10050436080.

The previous prime is 21225416579. The next prime is 21225416659. The reversal of 21225416648 is 84661452212.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 10612708324 + 10612708324 = 103018^2 + 103018^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=103018.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 7828013 + ... + 7830723.

Almost surely, 2^21225416648 is an apocalyptic number.

It is an amenable number.

21225416648 is a deficient number, since it is larger than the sum of its proper divisors (20792594947).

21225416648 is an frugal number, since it uses more digits than its factorization.

21225416648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5466 (or 2732 counting only the distinct ones).

The product of its digits is 184320, while the sum is 41.

The spelling of 21225416648 in words is "twenty-one billion, two hundred twenty-five million, four hundred sixteen thousand, six hundred forty-eight".