21450425444 has 24 divisors (see below), whose sum is σ = 45424431360. Its totient is φ = 8652272256.

The previous prime is 21450425411. The next prime is 21450425483. The reversal of 21450425444 is 44452405412.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22531484 + ... + 22532435.

It is an arithmetic number, because the mean of its divisors is an integer number (1892684640).

Almost surely, 2^21450425444 is an apocalyptic number.

It is an amenable number.

21450425444 is an abundant number, since it is smaller than the sum of its proper divisors (23974005916).

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

21450425444 is a wasteful number, since it uses less digits than its factorization.

21450425444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45063947 (or 45063945 counting only the distinct ones).

The product of its (nonzero) digits is 102400, while the sum is 35.

The spelling of 21450425444 in words is "twenty-one billion, four hundred fifty million, four hundred twenty-five thousand, four hundred forty-four".