215800780015 has 16 divisors (see below), whose sum is σ = 259219429632. Its totient is φ = 172468397824.

The previous prime is 215800779989. The next prime is 215800780049. The reversal of 215800780015 is 510087008512.

It is a cyclic number.

It is not a de Polignac number, because 215800780015 - 2³³ = 207210845423 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 (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26005347 + ... + 26013643.

It is an arithmetic number, because the mean of its divisors is an integer number (16201214352).

Almost surely, 2^215800780015 is an apocalyptic number.

215800780015 is a deficient number, since it is larger than the sum of its proper divisors (43418649617).

215800780015 is a wasteful number, since it uses less digits than its factorization.

215800780015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12866.

The product of its (nonzero) digits is 22400, while the sum is 37.

Adding to 215800780015 its reverse (510087008512), we get a palindrome (725887788527).

The spelling of 215800780015 in words is "two hundred fifteen billion, eight hundred million, seven hundred eighty thousand, fifteen".