21345350354345 has 4 divisors (see below), whose sum is σ = 25614420425220. Its totient is φ = 17076280283472.

The previous prime is 21345350354303. The next prime is 21345350354351. The reversal of 21345350354345 is 54345305354312.

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 15979678456681 + 5365671897664 = 3997459^2 + 2316392^2 .

It is a cyclic number.

It is not a de Polignac number, because 21345350354345 - 2⁶ = 21345350354281 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21345350354345.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2134535035430 + ... + 2134535035439.

It is an arithmetic number, because the mean of its divisors is an integer number (6403605106305).

Almost surely, 2^{21345350354345} is an apocalyptic number.

It is an amenable number.

21345350354345 is a deficient number, since it is larger than the sum of its proper divisors (4269070070875).

21345350354345 is an equidigital number, since it uses as much as digits as its factorization.

21345350354345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4269070070874.

The product of its (nonzero) digits is 6480000, while the sum is 47.

The spelling of 21345350354345 in words is "twenty-one trillion, three hundred forty-five billion, three hundred fifty million, three hundred fifty-four thousand, three hundred forty-five".