21111010000221 has 4 divisors (see below), whose sum is σ = 28148013333632. Its totient is φ = 14074006666812.

The previous prime is 21111010000193. The next prime is 21111010000229. The reversal of 21111010000221 is 12200001011112.

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 not a de Polignac number, because 21111010000221 - 2⁵ = 21111010000189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21111010000197 and 21111010000206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111010000229) 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, 3518501666701 + ... + 3518501666706.

It is an arithmetic number, because the mean of its divisors is an integer number (7037003333408).

Almost surely, 2^{21111010000221} is an apocalyptic number.

It is an amenable number.

21111010000221 is a deficient number, since it is larger than the sum of its proper divisors (7037003333411).

21111010000221 is an equidigital number, since it uses as much as digits as its factorization.

21111010000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7037003333410.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21111010000221 its reverse (12200001011112), we get a palindrome (33311011011333).

The spelling of 21111010000221 in words is "twenty-one trillion, one hundred eleven billion, ten million, two hundred twenty-one", and thus it is an aban number.