21004221335055 has 16 divisors (see below), whose sum is σ = 38407719012864. Its totient is φ = 9601929753120.

The previous prime is 21004221335051. The next prime is 21004221335093. The reversal of 21004221335055 is 55053312240012.

It is not a de Polignac number, because 21004221335055 - 2² = 21004221335051 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21004221335051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100020101491 + ... + 100020101700.

It is an arithmetic number, because the mean of its divisors is an integer number (2400482438304).

Almost surely, 2^{21004221335055} is an apocalyptic number.

21004221335055 is a deficient number, since it is larger than the sum of its proper divisors (17403497677809).

21004221335055 is a wasteful number, since it uses less digits than its factorization.

21004221335055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200040203206.

The product of its (nonzero) digits is 36000, while the sum is 33.

Adding to 21004221335055 its reverse (55053312240012), we get a palindrome (76057533575067).

The spelling of 21004221335055 in words is "twenty-one trillion, four billion, two hundred twenty-one million, three hundred thirty-five thousand, fifty-five".