21001120111001 has 8 divisors (see below), whose sum is σ = 21063154855200. Its totient is φ = 20939133441600.

The previous prime is 21001120110973. The next prime is 21001120111003. The reversal of 21001120111001 is 10011102110012.

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 21001120111001 - 2¹⁸ = 21001119848857 is a prime.

It is a super-2 number, since 2×21001120111001² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21001120111003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11143631 + ... + 12891188.

It is an arithmetic number, because the mean of its divisors is an integer number (2632894356900).

Almost surely, 2^{21001120111001} is an apocalyptic number.

It is an amenable number.

21001120111001 is a deficient number, since it is larger than the sum of its proper divisors (62034744199).

21001120111001 is a wasteful number, since it uses less digits than its factorization.

21001120111001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24037399.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21001120111001 its reverse (10011102110012), we get a palindrome (31012222221013).

The spelling of 21001120111001 in words is "twenty-one trillion, one billion, one hundred twenty million, one hundred eleven thousand, one".