21331020343345 has 8 divisors (see below), whose sum is σ = 25597783175976. Its totient is φ = 17064443765376.

The previous prime is 21331020343331. The next prime is 21331020343393. The reversal of 21331020343345 is 54334302013312.

It can be written as a sum of positive squares in 4 ways, for example, as 6109419532176 + 15221600811169 = 2471724^2 + 3901487^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21331020343345 is a prime.

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 21331020343345.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46311582 + ... + 46769911.

It is an arithmetic number, because the mean of its divisors is an integer number (3199722896997).

Almost surely, 2^{21331020343345} is an apocalyptic number.

It is an amenable number.

21331020343345 is a deficient number, since it is larger than the sum of its proper divisors (4266762832631).

21331020343345 is an equidigital number, since it uses as much as digits as its factorization.

21331020343345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93127331.

The product of its (nonzero) digits is 77760, while the sum is 34.

Adding to 21331020343345 its reverse (54334302013312), we get a palindrome (75665322356657).

The spelling of 21331020343345 in words is "twenty-one trillion, three hundred thirty-one billion, twenty million, three hundred forty-three thousand, three hundred forty-five".