21221002002021 has 8 divisors (see below), whose sum is σ = 29959061649984. Its totient is φ = 13315138511040.

The previous prime is 21221002002007. The next prime is 21221002002023. The reversal of 21221002002021 is 12020020012212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21221002002021 - 2²⁷ = 21220867784293 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221002002023) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 208049039185 + ... + 208049039286.

It is an arithmetic number, because the mean of its divisors is an integer number (3744882706248).

Almost surely, 2^{21221002002021} is an apocalyptic number.

It is an amenable number.

21221002002021 is a deficient number, since it is larger than the sum of its proper divisors (8738059647963).

21221002002021 is a wasteful number, since it uses less digits than its factorization.

21221002002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416098078491.

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

Adding to 21221002002021 its reverse (12020020012212), we get a palindrome (33241022014233).

The spelling of 21221002002021 in words is "twenty-one trillion, two hundred twenty-one billion, two million, two thousand, twenty-one".