20101211001 has 12 divisors (see below), whose sum is σ = 29819815012. Its totient is φ = 13038623136.

The previous prime is 20101210993. The next prime is 20101211017. The reversal of 20101211001 is 10011210102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 9736952976 + 10364258025 = 98676^2 + 101805^2 .

It is not a de Polignac number, because 20101211001 - 2³ = 20101210993 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20101211041) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30181666 + ... + 30182331.

Almost surely, 2^20101211001 is an apocalyptic number.

It is an amenable number.

20101211001 is a deficient number, since it is larger than the sum of its proper divisors (9718604011).

20101211001 is a wasteful number, since it uses less digits than its factorization.

20101211001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60364040 (or 60364037 counting only the distinct ones).

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

Adding to 20101211001 its reverse (10011210102), we get a palindrome (30112421103).

The spelling of 20101211001 in words is "twenty billion, one hundred one million, two hundred eleven thousand, one".