21001221202002 has 16 divisors (see below), whose sum is σ = 42002504195232. Its totient is φ = 7000396768800.

The previous prime is 21001221201991. The next prime is 21001221202019. The reversal of 21001221202002 is 20020212210012.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2663502 + ... + 7006902.

It is an arithmetic number, because the mean of its divisors is an integer number (2625156512202).

Almost surely, 2^{21001221202002} is an apocalyptic number.

21001221202002 is an abundant number, since it is smaller than the sum of its proper divisors (21001282993230).

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

21001221202002 is a wasteful number, since it uses less digits than its factorization.

21001221202002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5149273.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21001221202002 its reverse (20020212210012), we get a palindrome (41021433412014).

The spelling of 21001221202002 in words is "twenty-one trillion, one billion, two hundred twenty-one million, two hundred two thousand, two".