21440121020550 has 72 divisors (see below), whose sum is σ = 59588750183040. Its totient is φ = 5520215064000.

The previous prime is 21440121020509. The next prime is 21440121020611. The reversal of 21440121020550 is 5502012104412.

It is a happy number.

21440121020550 is a `hidden beast` number, since 2 + 1 + 4 + 4 + 0 + 1 + 2 + 102 + 0 + 550 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 821447526 + ... + 821473625.

It is an arithmetic number, because the mean of its divisors is an integer number (827621530320).

Almost surely, 2^{21440121020550} is an apocalyptic number.

21440121020550 is an abundant number, since it is smaller than the sum of its proper divisors (38148629162490).

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

21440121020550 is a wasteful number, since it uses less digits than its factorization.

21440121020550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1642921198 (or 1642921190 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

Adding to 21440121020550 its reverse (5502012104412), we get a palindrome (26942133124962).

The spelling of 21440121020550 in words is "twenty-one trillion, four hundred forty billion, one hundred twenty-one million, twenty thousand, five hundred fifty".