21621350205341 has 4 divisors (see below), whose sum is σ = 21621440929500. Its totient is φ = 21621259481184.

The previous prime is 21621350205337. The next prime is 21621350205353. The reversal of 21621350205341 is 14350205312612.

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 726166439716 + 20895183765625 = 852154^2 + 4571125^2 .

It is a cyclic number.

It is not a de Polignac number, because 21621350205341 - 2² = 21621350205337 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621350205311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45003656 + ... + 45481553.

It is an arithmetic number, because the mean of its divisors is an integer number (5405360232375).

Almost surely, 2^{21621350205341} is an apocalyptic number.

It is an amenable number.

21621350205341 is a deficient number, since it is larger than the sum of its proper divisors (90724159).

21621350205341 is an equidigital number, since it uses as much as digits as its factorization.

21621350205341 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90724158.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21621350205341 its reverse (14350205312612), we get a palindrome (35971555517953).

The spelling of 21621350205341 in words is "twenty-one trillion, six hundred twenty-one billion, three hundred fifty million, two hundred five thousand, three hundred forty-one".