16865402005 has 4 divisors (see below), whose sum is σ = 20238482412. Its totient is φ = 13492321600.

The previous prime is 16865401997. The next prime is 16865402063. The reversal of 16865402005 is 50020456861.

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 3585374884 + 13280027121 = 59878^2 + 115239^2 .

It is not a de Polignac number, because 16865402005 - 2³ = 16865401997 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 1686540196 + ... + 1686540205.

It is an arithmetic number, because the mean of its divisors is an integer number (5059620603).

Almost surely, 2^16865402005 is an apocalyptic number.

It is an amenable number.

16865402005 is a deficient number, since it is larger than the sum of its proper divisors (3373080407).

16865402005 is an equidigital number, since it uses as much as digits as its factorization.

16865402005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3373080406.

The product of its (nonzero) digits is 57600, while the sum is 37.

Adding to 16865402005 its reverse (50020456861), we get a palindrome (66885858866).

The spelling of 16865402005 in words is "sixteen billion, eight hundred sixty-five million, four hundred two thousand, five".