21301320133 has 4 divisors (see below), whose sum is σ = 21309582240. Its totient is φ = 21293058028.

The previous prime is 21301320121. The next prime is 21301320143. The reversal of 21301320133 is 33102310312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21301320133 is a prime.

It is a super-2 number, since 2×21301320133² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21301320133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21301320143) 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, 4127185 + ... + 4132342.

It is an arithmetic number, because the mean of its divisors is an integer number (5327395560).

Almost surely, 2^21301320133 is an apocalyptic number.

It is an amenable number.

21301320133 is a deficient number, since it is larger than the sum of its proper divisors (8262107).

21301320133 is an equidigital number, since it uses as much as digits as its factorization.

21301320133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8262106.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21301320133 its reverse (33102310312), we get a palindrome (54403630445).

The spelling of 21301320133 in words is "twenty-one billion, three hundred one million, three hundred twenty thousand, one hundred thirty-three".