21122110210021 has 4 divisors (see below), whose sum is σ = 22040462827872. Its totient is φ = 20203757592172.

The previous prime is 21122110209971. The next prime is 21122110210027. The reversal of 21122110210021 is 12001201122112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21122110210021 - 2²³ = 21122101821413 is a prime.

It is a super-2 number, since 2×21122110210021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21122110209977 and 21122110210004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122110210027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 459176308891 + ... + 459176308936.

It is an arithmetic number, because the mean of its divisors is an integer number (5510115706968).

Almost surely, 2^{21122110210021} is an apocalyptic number.

It is an amenable number.

21122110210021 is a deficient number, since it is larger than the sum of its proper divisors (918352617851).

21122110210021 is an equidigital number, since it uses as much as digits as its factorization.

21122110210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 918352617850.

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

Adding to 21122110210021 its reverse (12001201122112), we get a palindrome (33123311332133).

The spelling of 21122110210021 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred ten million, two hundred ten thousand, twenty-one".