21020021210001 has 16 divisors (see below), whose sum is σ = 30575178336960. Its totient is φ = 12739155947520.

The previous prime is 21020021209933. The next prime is 21020021210009. The reversal of 21020021210001 is 10001212002012.

It is not a de Polignac number, because 21020021210001 - 2⁹ = 21020021209489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21020021210009) 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, 4562896 + ... + 7928433.

It is an arithmetic number, because the mean of its divisors is an integer number (1910948646060).

Almost surely, 2^{21020021210001} is an apocalyptic number.

It is an amenable number.

21020021210001 is a deficient number, since it is larger than the sum of its proper divisors (9555157126959).

21020021210001 is a wasteful number, since it uses less digits than its factorization.

21020021210001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12542336.

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

Adding to 21020021210001 its reverse (10001212002012), we get a palindrome (31021233212013).

The spelling of 21020021210001 in words is "twenty-one trillion, twenty billion, twenty-one million, two hundred ten thousand, one".