21440254550 has 96 divisors (see below), whose sum is σ = 49316843520. Its totient is φ = 6817910400.

The previous prime is 21440254523. The next prime is 21440254559. The reversal of 21440254550 is 5545204412.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440254559) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 56939 + ... + 214761.

It is an arithmetic number, because the mean of its divisors is an integer number (513717120).

Almost surely, 2^21440254550 is an apocalyptic number.

21440254550 is an abundant number, since it is smaller than the sum of its proper divisors (27876588970).

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

21440254550 is a wasteful number, since it uses less digits than its factorization.

21440254550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157878 (or 157873 counting only the distinct ones).

The product of its (nonzero) digits is 32000, while the sum is 32.

Adding to 21440254550 its reverse (5545204412), we get a palindrome (26985458962).

The spelling of 21440254550 in words is "twenty-one billion, four hundred forty million, two hundred fifty-four thousand, five hundred fifty".