21020021222001 has 32 divisors (see below), whose sum is σ = 28406816954880. Its totient is φ = 13824725289984.

The previous prime is 21020021221987. The next prime is 21020021222003. The reversal of 21020021222001 is 10022212002012.

It is not a de Polignac number, because 21020021222001 - 2⁹ = 21020021221489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21020021222003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 70916830 + ... + 71212616.

It is an arithmetic number, because the mean of its divisors is an integer number (887713029840).

Almost surely, 2^{21020021222001} is an apocalyptic number.

It is an amenable number.

21020021222001 is a deficient number, since it is larger than the sum of its proper divisors (7386795732879).

21020021222001 is a wasteful number, since it uses less digits than its factorization.

21020021222001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297005.

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

Adding to 21020021222001 its reverse (10022212002012), we get a palindrome (31042233224013).

The spelling of 21020021222001 in words is "twenty-one trillion, twenty billion, twenty-one million, two hundred twenty-two thousand, one".