21910405899 has 4 divisors (see below), whose sum is σ = 29213874536. Its totient is φ = 14606937264.

The previous prime is 21910405879. The next prime is 21910405901. The reversal of 21910405899 is 99850401912.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21910405899 - 2¹² = 21910401803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21910405879) by changing a digit.

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, 3651734314 + ... + 3651734319.

It is an arithmetic number, because the mean of its divisors is an integer number (7303468634).

Almost surely, 2^21910405899 is an apocalyptic number.

21910405899 is a deficient number, since it is larger than the sum of its proper divisors (7303468637).

21910405899 is an equidigital number, since it uses as much as digits as its factorization.

21910405899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7303468636.

The product of its (nonzero) digits is 233280, while the sum is 48.

The spelling of 21910405899 in words is "twenty-one billion, nine hundred ten million, four hundred five thousand, eight hundred ninety-nine".