21122021001221 has 8 divisors (see below), whose sum is σ = 24139881537024. Its totient is φ = 18104267706480.

The previous prime is 21122021001199. The next prime is 21122021001223. The reversal of 21122021001221 is 12210012022112.

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 21122021001221 - 2⁶ = 21122021001157 is a prime.

It is a super-2 number, since 2×21122021001221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21122021001221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122021001223) 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, 26387765 + ... + 27176426.

It is an arithmetic number, because the mean of its divisors is an integer number (3017485192128).

Almost surely, 2^{21122021001221} is an apocalyptic number.

It is an amenable number.

21122021001221 is a deficient number, since it is larger than the sum of its proper divisors (3017860535803).

21122021001221 is an equidigital number, since it uses as much as digits as its factorization.

21122021001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53620531.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21122021001221 its reverse (12210012022112), we get a palindrome (33332033023333).

The spelling of 21122021001221 in words is "twenty-one trillion, one hundred twenty-two billion, twenty-one million, one thousand, two hundred twenty-one".