21001010111021 has 8 divisors (see below), whose sum is σ = 21855273793920. Its totient is φ = 20155419156208.

The previous prime is 21001010110981. The next prime is 21001010111063. The reversal of 21001010111021 is 12011101010012.

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 21001010111021 - 2²² = 21001005916717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001010110993 and 21001010111011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001010111321) 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, 2168177081 + ... + 2168186766.

It is an arithmetic number, because the mean of its divisors is an integer number (2731909224240).

Almost surely, 2^{21001010111021} is an apocalyptic number.

It is an amenable number.

21001010111021 is a deficient number, since it is larger than the sum of its proper divisors (854263682899).

21001010111021 is a wasteful number, since it uses less digits than its factorization.

21001010111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4336364043.

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

Adding to 21001010111021 its reverse (12011101010012), we get a palindrome (33012111121033).

The spelling of 21001010111021 in words is "twenty-one trillion, one billion, ten million, one hundred eleven thousand, twenty-one".