21033520345 has 16 divisors (see below), whose sum is σ = 26121580560. Its totient is φ = 16239734784.

The previous prime is 21033520327. The next prime is 21033520373. The reversal of 21033520345 is 54302533012.

It can be written as a sum of positive squares in 8 ways, for example, as 2650499289 + 18383021056 = 51483^2 + 135584^2 .

It is a cyclic number.

It is not a de Polignac number, because 21033520345 - 2²⁵ = 20999965913 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 329257 + ... + 387913.

It is an arithmetic number, because the mean of its divisors is an integer number (1632598785).

Almost surely, 2^21033520345 is an apocalyptic number.

It is an amenable number.

21033520345 is a deficient number, since it is larger than the sum of its proper divisors (5088060215).

21033520345 is a wasteful number, since it uses less digits than its factorization.

21033520345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61164.

The product of its (nonzero) digits is 10800, while the sum is 28.

The spelling of 21033520345 in words is "twenty-one billion, thirty-three million, five hundred twenty thousand, three hundred forty-five".