21220121002008 has 64 divisors (see below), whose sum is σ = 53491042725120. Its totient is φ = 7014839216000.

The previous prime is 21220121002001. The next prime is 21220121002009. The reversal of 21220121002008 is 80020012102212.

It is a super-2 number, since 2×21220121002008² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220121002001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5745318 + ... + 8686133.

It is an arithmetic number, because the mean of its divisors is an integer number (835797542580).

Almost surely, 2^{21220121002008} is an apocalyptic number.

It is an amenable number.

21220121002008 is an abundant number, since it is smaller than the sum of its proper divisors (32270921723112).

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

21220121002008 is a wasteful number, since it uses less digits than its factorization.

21220121002008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14431968 (or 14431964 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The spelling of 21220121002008 in words is "twenty-one trillion, two hundred twenty billion, one hundred twenty-one million, two thousand, eight".