216860904 has 96 divisors (see below), whose sum is σ = 635150880. Its totient is φ = 66448512.

The previous prime is 216860893. The next prime is 216860921. The reversal of 216860904 is 409068612.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 414387 + ... + 414909.

It is an arithmetic number, because the mean of its divisors is an integer number (6616155).

Almost surely, 2^216860904 is an apocalyptic number.

216860904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216860904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317575440).

216860904 is an abundant number, since it is smaller than the sum of its proper divisors (418289976).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216860904 is a wasteful number, since it uses less digits than its factorization.

216860904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991 (or 984 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 216860904 is about 14726.1978799689. The cubic root of 216860904 is about 600.7960766362.

The spelling of 216860904 in words is "two hundred sixteen million, eight hundred sixty thousand, nine hundred four".