21010112001 has 6 divisors (see below), whose sum is σ = 30347939570. Its totient is φ = 14006741328.

The previous prime is 21010111981. The next prime is 21010112017. The reversal of 21010112001 is 10021101012.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 13798026225 + 7212085776 = 117465^2 + 84924^2 .

It is not a de Polignac number, because 21010112001 - 2⁶ = 21010111937 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 2334456889 = 21010112001 / (2 + 1 + 0 + 1 + 0 + 1 + 1 + 2 + 0 + 0 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21010112401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1167228436 + ... + 1167228453.

Almost surely, 2^21010112001 is an apocalyptic number.

It is an amenable number.

21010112001 is a deficient number, since it is larger than the sum of its proper divisors (9337827569).

21010112001 is a wasteful number, since it uses less digits than its factorization.

21010112001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2334456895 (or 2334456892 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21010112001 its reverse (10021101012), we get a palindrome (31031213013).

It can be divided in two parts, 2101011 and 2001, that added together give a palindrome (2103012).

The spelling of 21010112001 in words is "twenty-one billion, ten million, one hundred twelve thousand, one".