215842887 has 20 divisors (see below), whose sum is σ = 347236120. Its totient is φ = 132825744.

The previous prime is 215842877. The next prime is 215842903. The reversal of 215842887 is 788248512.

It is a happy number.

215842887 is a `hidden beast` number, since 215 + 8 + 428 + 8 + 7 = 666.

It is not a de Polignac number, because 215842887 - 2⁸ = 215842631 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215842877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 101437 + ... + 103542.

It is an arithmetic number, because the mean of its divisors is an integer number (17361806).

Almost surely, 2^215842887 is an apocalyptic number.

215842887 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

215842887 is a deficient number, since it is larger than the sum of its proper divisors (131393233).

215842887 is a wasteful number, since it uses less digits than its factorization.

215842887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205004 (or 204995 counting only the distinct ones).

The product of its digits is 286720, while the sum is 45.

The square root of 215842887 is about 14691.5923915687. The cubic root of 215842887 is about 599.8544897141.

Subtracting 215842887 from its reverse (788248512), we obtain a square (572405625 = 23925²).

The spelling of 215842887 in words is "two hundred fifteen million, eight hundred forty-two thousand, eight hundred eighty-seven".