21001002122111 has 8 divisors (see below), whose sum is σ = 22912865985024. Its totient is φ = 19089585234520.

The previous prime is 21001002122077. The next prime is 21001002122143. The reversal of 21001002122111 is 11122120010012.

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 21001002122111 - 2²² = 21000997927807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001002122011) 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, 111645581 + ... + 111833526.

It is an arithmetic number, because the mean of its divisors is an integer number (2864108248128).

Almost surely, 2^{21001002122111} is an apocalyptic number.

21001002122111 is a deficient number, since it is larger than the sum of its proper divisors (1911863862913).

21001002122111 is a wasteful number, since it uses less digits than its factorization.

21001002122111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223487661.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21001002122111 its reverse (11122120010012), we get a palindrome (32123122132123).

The spelling of 21001002122111 in words is "twenty-one trillion, one billion, two million, one hundred twenty-two thousand, one hundred eleven".