21311013001 has 4 divisors (see below), whose sum is σ = 21335880852. Its totient is φ = 21286145152.

The previous prime is 21311012977. The next prime is 21311013011. The reversal of 21311013001 is 10031011312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18462015625 + 2848997376 = 135875^2 + 53376^2 .

It is a cyclic number.

It is not a de Polignac number, because 21311013001 - 2¹⁵ = 21310980233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21311013011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12432640 + ... + 12434353.

It is an arithmetic number, because the mean of its divisors is an integer number (5333970213).

Almost surely, 2^21311013001 is an apocalyptic number.

It is an amenable number.

21311013001 is a deficient number, since it is larger than the sum of its proper divisors (24867851).

21311013001 is an equidigital number, since it uses as much as digits as its factorization.

21311013001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24867850.

The product of its (nonzero) digits is 18, while the sum is 13.

Adding to 21311013001 its reverse (10031011312), we get a palindrome (31342024313).

The spelling of 21311013001 in words is "twenty-one billion, three hundred eleven million, thirteen thousand, one".