21000002220021 has 16 divisors (see below), whose sum is σ = 30596282192448. Its totient is φ = 12706097232000.

The previous prime is 21000002220013. The next prime is 21000002220047. The reversal of 21000002220021 is 12002220000012.

It is not a de Polignac number, because 21000002220021 - 2³ = 21000002220013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000002219979 and 21000002220006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000002222021) 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, 529400886 + ... + 529440551.

It is an arithmetic number, because the mean of its divisors is an integer number (1912267637028).

Almost surely, 2^{21000002220021} is an apocalyptic number.

It is an amenable number.

21000002220021 is a deficient number, since it is larger than the sum of its proper divisors (9596279972427).

21000002220021 is a wasteful number, since it uses less digits than its factorization.

21000002220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058842052.

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21000002220021 its reverse (12002220000012), we get a palindrome (33002222220033).

The spelling of 21000002220021 in words is "twenty-one trillion, two million, two hundred twenty thousand, twenty-one".