216876820 has 24 divisors (see below), whose sum is σ = 482232744. Its totient is φ = 81647616.

The previous prime is 216876799. The next prime is 216876823. The reversal of 216876820 is 28678612.

216876820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 97061904 + 119814916 = 9852^2 + 10946^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216876823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 318597 + ... + 319276.

It is an arithmetic number, because the mean of its divisors is an integer number (20093031).

Almost surely, 2^216876820 is an apocalyptic number.

216876820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216876820 is an abundant number, since it is smaller than the sum of its proper divisors (265355924).

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

216876820 is a wasteful number, since it uses less digits than its factorization.

216876820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637899 (or 637897 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 216876820 is about 14726.7382675187. The cubic root of 216876820 is about 600.8107742853.

The spelling of 216876820 in words is "two hundred sixteen million, eight hundred seventy-six thousand, eight hundred twenty".