21941503805 has 32 divisors (see below), whose sum is σ = 28917907200. Its totient is φ = 15882964992.

The previous prime is 21941503769. The next prime is 21941503817. The reversal of 21941503805 is 50830514912.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21941503805 - 2⁶ = 21941503741 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1368797 + ... + 1384733.

It is an arithmetic number, because the mean of its divisors is an integer number (903684600).

Almost surely, 2^21941503805 is an apocalyptic number.

It is an amenable number.

21941503805 is a deficient number, since it is larger than the sum of its proper divisors (6976403395).

21941503805 is a wasteful number, since it uses less digits than its factorization.

21941503805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16373.

The product of its (nonzero) digits is 43200, while the sum is 38.

The spelling of 21941503805 in words is "twenty-one billion, nine hundred forty-one million, five hundred three thousand, eight hundred five".