21121111000221 has 8 divisors (see below), whose sum is σ = 28194265366560. Its totient is φ = 14064348650352.

The previous prime is 21121111000097. The next prime is 21121111000279. The reversal of 21121111000221 is 12200011112112.

It is a happy number.

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

It is not a de Polignac number, because 21121111000221 - 2¹³ = 21121110992029 is a prime.

It is a super-2 number, since 2×21121111000221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21121111000221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121111000291) 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, 4098001110 + ... + 4098006263.

It is an arithmetic number, because the mean of its divisors is an integer number (3524283170820).

Almost surely, 2^{21121111000221} is an apocalyptic number.

It is an amenable number.

21121111000221 is a deficient number, since it is larger than the sum of its proper divisors (7073154366339).

21121111000221 is an equidigital number, since it uses as much as digits as its factorization.

21121111000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8196008235.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21121111000221 its reverse (12200011112112), we get a palindrome (33321122112333).

The spelling of 21121111000221 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred eleven million, two hundred twenty-one", and thus it is an aban number.