21033736205 has 4 divisors (see below), whose sum is σ = 25240483452. Its totient is φ = 16826988960.

The previous prime is 21033736153. The next prime is 21033736211. The reversal of 21033736205 is 50263733012.

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 2459862409 + 18573873796 = 49597^2 + 136286^2 .

It is not a de Polignac number, because 21033736205 - 2³² = 16738768909 is a prime.

It is a Duffinian number.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 2103373616 + ... + 2103373625.

It is an arithmetic number, because the mean of its divisors is an integer number (6310120863).

Almost surely, 2^21033736205 is an apocalyptic number.

It is an amenable number.

21033736205 is a deficient number, since it is larger than the sum of its proper divisors (4206747247).

21033736205 is an equidigital number, since it uses as much as digits as its factorization.

21033736205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4206747246.

The product of its (nonzero) digits is 22680, while the sum is 32.

The spelling of 21033736205 in words is "twenty-one billion, thirty-three million, seven hundred thirty-six thousand, two hundred five".