21001203133 has 4 divisors (see below), whose sum is σ = 21028513660. Its totient is φ = 20973892608.

The previous prime is 21001203109. The next prime is 21001203149. The reversal of 21001203133 is 33130210012.

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 15762049209 + 5239153924 = 125547^2 + 72382^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21001203133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001203163) 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, 13654110 + ... + 13655647.

It is an arithmetic number, because the mean of its divisors is an integer number (5257128415).

Almost surely, 2^21001203133 is an apocalyptic number.

It is an amenable number.

21001203133 is a deficient number, since it is larger than the sum of its proper divisors (27310527).

21001203133 is an equidigital number, since it uses as much as digits as its factorization.

21001203133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27310526.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 21001203133 its reverse (33130210012), we get a palindrome (54131413145).

The spelling of 21001203133 in words is "twenty-one billion, one million, two hundred three thousand, one hundred thirty-three".