21021110020001 has 64 divisors (see below), whose sum is σ = 27980949964800. Its totient is φ = 15329956755456.

The previous prime is 21021110019983. The next prime is 21021110020063. The reversal of 21021110020001 is 10002001112012.

It is not a de Polignac number, because 21021110020001 - 2⁶ = 21021110019937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21021110025001) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8832866 + ... + 10957268.

It is an arithmetic number, because the mean of its divisors is an integer number (437202343200).

Almost surely, 2^{21021110020001} is an apocalyptic number.

It is an amenable number.

21021110020001 is a deficient number, since it is larger than the sum of its proper divisors (6959839944799).

21021110020001 is a wasteful number, since it uses less digits than its factorization.

21021110020001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2124598.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21021110020001 its reverse (10002001112012), we get a palindrome (31023111132013).

The spelling of 21021110020001 in words is "twenty-one trillion, twenty-one billion, one hundred ten million, twenty thousand, one".