21001100022021 has 8 divisors (see below), whose sum is σ = 32001676224064. Its totient is φ = 12000628584000.

The previous prime is 21001100021999. The next prime is 21001100022073. The reversal of 21001100022021 is 12022000110012.

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

It is not a de Polignac number, because 21001100022021 - 2¹⁷ = 21001099890949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001100021988 and 21001100022006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001100022821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 500026190980 + ... + 500026191021.

It is an arithmetic number, because the mean of its divisors is an integer number (4000209528008).

Almost surely, 2^{21001100022021} is an apocalyptic number.

21001100022021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21001100022021 is a deficient number, since it is larger than the sum of its proper divisors (11000576202043).

21001100022021 is a wasteful number, since it uses less digits than its factorization.

21001100022021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1000052382011.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21001100022021 its reverse (12022000110012), we get a palindrome (33023100132033).

The spelling of 21001100022021 in words is "twenty-one trillion, one billion, one hundred million, twenty-two thousand, twenty-one".