21350202443 has 4 divisors (see below), whose sum is σ = 21561590688. Its totient is φ = 21138814200.

The previous prime is 21350202439. The next prime is 21350202509. The reversal of 21350202443 is 34420205312.

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

It is a cyclic number.

It is not a de Polignac number, because 21350202443 - 2² = 21350202439 is a prime.

It is a super-2 number, since 2×21350202443² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21350202343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105693971 + ... + 105694172.

It is an arithmetic number, because the mean of its divisors is an integer number (5390397672).

Almost surely, 2^21350202443 is an apocalyptic number.

21350202443 is a deficient number, since it is larger than the sum of its proper divisors (211388245).

21350202443 is a wasteful number, since it uses less digits than its factorization.

21350202443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211388244.

The product of its (nonzero) digits is 5760, while the sum is 26.

Adding to 21350202443 its reverse (34420205312), we get a palindrome (55770407755).

The spelling of 21350202443 in words is "twenty-one billion, three hundred fifty million, two hundred two thousand, four hundred forty-three".