21201112110021 has 8 divisors (see below), whose sum is σ = 28269275308224. Its totient is φ = 14133511825920.

The previous prime is 21201112109999. The next prime is 21201112110023. The reversal of 21201112110021 is 12001121110212.

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 21201112110021 - 2⁷ = 21201112109893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201112110023) 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, 140640636 + ... + 140791301.

It is an arithmetic number, because the mean of its divisors is an integer number (3533659413528).

Almost surely, 2^{21201112110021} is an apocalyptic number.

It is an amenable number.

21201112110021 is a deficient number, since it is larger than the sum of its proper divisors (7068163198203).

21201112110021 is a wasteful number, since it uses less digits than its factorization.

21201112110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281457051.

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

Adding to 21201112110021 its reverse (12001121110212), we get a palindrome (33202233220233).

The spelling of 21201112110021 in words is "twenty-one trillion, two hundred one billion, one hundred twelve million, one hundred ten thousand, twenty-one".