21555355121104 has 40 divisors (see below), whose sum is σ = 47739321640640. Its totient is φ = 9236149970688.

The previous prime is 21555355121089. The next prime is 21555355121117. The reversal of 21555355121104 is 40112155355512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18809394 + ... + 19922449.

It is an arithmetic number, because the mean of its divisors is an integer number (1193483041016).

Almost surely, 2^{21555355121104} is an apocalyptic number.

It is an amenable number.

21555355121104 is an abundant number, since it is smaller than the sum of its proper divisors (26183966519536).

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

21555355121104 is a wasteful number, since it uses less digits than its factorization.

21555355121104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38736827 (or 38736821 counting only the distinct ones).

The product of its (nonzero) digits is 150000, while the sum is 40.

The spelling of 21555355121104 in words is "twenty-one trillion, five hundred fifty-five billion, three hundred fifty-five million, one hundred twenty-one thousand, one hundred four".