21010110011001 has 48 divisors (see below), whose sum is σ = 30780455706000. Its totient is φ = 13808114141184.

The previous prime is 21010110010979. The next prime is 21010110011017. The reversal of 21010110011001 is 10011001101012.

It can be written as a sum of positive squares in 8 ways, for example, as 1269407822400 + 19740702188601 = 1126680^2 + 4443051^2 .

It is not a de Polignac number, because 21010110011001 - 2⁶ = 21010110010937 is a prime.

It is a super-3 number, since 3×21010110011001³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21010110011021) 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 47 ways as a sum of consecutive naturals, for example, 382329075 + ... + 382384023.

It is an arithmetic number, because the mean of its divisors is an integer number (641259493875).

Almost surely, 2^{21010110011001} is an apocalyptic number.

It is an amenable number.

21010110011001 is a deficient number, since it is larger than the sum of its proper divisors (9770345694999).

21010110011001 is a wasteful number, since it uses less digits than its factorization.

21010110011001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56458 (or 56455 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

Adding to 21010110011001 its reverse (10011001101012), we get a palindrome (31021111112013).

The spelling of 21010110011001 in words is "twenty-one trillion, ten billion, one hundred ten million, eleven thousand, one".