21111012010221 has 8 divisors (see below), whose sum is σ = 32169161158464. Its totient is φ = 12063435434400.

The previous prime is 21111012010199. The next prime is 21111012010229. The reversal of 21111012010221 is 12201021011112.

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 21111012010221 - 2⁷ = 21111012010093 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21111012010221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111012010229) 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, 502643143080 + ... + 502643143121.

It is an arithmetic number, because the mean of its divisors is an integer number (4021145144808).

Almost surely, 2^{21111012010221} is an apocalyptic number.

21111012010221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21111012010221 is a deficient number, since it is larger than the sum of its proper divisors (11058149148243).

21111012010221 is a wasteful number, since it uses less digits than its factorization.

21111012010221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1005286286211.

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

Adding to 21111012010221 its reverse (12201021011112), we get a palindrome (33312033021333).

The spelling of 21111012010221 in words is "twenty-one trillion, one hundred eleven billion, twelve million, ten thousand, two hundred twenty-one".