21243221450 has 48 divisors (see below), whose sum is σ = 43145943840. Its totient is φ = 7717368000.

The previous prime is 21243221449. The next prime is 21243221497. The reversal of 21243221450 is 5412234212.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 569885 + ... + 606015.

It is an arithmetic number, because the mean of its divisors is an integer number (898873830).

Almost surely, 2^21243221450 is an apocalyptic number.

21243221450 is an abundant number, since it is smaller than the sum of its proper divisors (21902722390).

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

21243221450 is a wasteful number, since it uses less digits than its factorization.

21243221450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37223 (or 37218 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

Adding to 21243221450 its reverse (5412234212), we get a palindrome (26655455662).

The spelling of 21243221450 in words is "twenty-one billion, two hundred forty-three million, two hundred twenty-one thousand, four hundred fifty".