21210021211021 has 8 divisors (see below), whose sum is σ = 21664031235840. Its totient is φ = 20756125060368.

The previous prime is 21210021210967. The next prime is 21210021211031. The reversal of 21210021211021 is 12011212001212.

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

It is a cyclic number.

It is not a de Polignac number, because 21210021211021 - 2⁷ = 21210021210893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21210021210986 and 21210021211004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210021211031) 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, 28091986 + ... + 28837123.

It is an arithmetic number, because the mean of its divisors is an integer number (2708003904480).

Almost surely, 2^{21210021211021} is an apocalyptic number.

It is an amenable number.

21210021211021 is a deficient number, since it is larger than the sum of its proper divisors (454010024819).

21210021211021 is an equidigital number, since it uses as much as digits as its factorization.

21210021211021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56937083.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21210021211021 its reverse (12011212001212), we get a palindrome (33221233212233).

The spelling of 21210021211021 in words is "twenty-one trillion, two hundred ten billion, twenty-one million, two hundred eleven thousand, twenty-one".