216556860 has 48 divisors (see below), whose sum is σ = 653004576. Its totient is φ = 53306112.

The previous prime is 216556817. The next prime is 216556867. The reversal of 216556860 is 68655612.

216556860 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×216556860² = 93793747226119200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216556867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 138039 + ... + 139598.

It is an arithmetic number, because the mean of its divisors is an integer number (13604262).

Almost surely, 2^216556860 is an apocalyptic number.

216556860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216556860 is an abundant number, since it is smaller than the sum of its proper divisors (436447716).

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

216556860 is a wasteful number, since it uses less digits than its factorization.

216556860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277662 (or 277660 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 39.

The square root of 216556860 is about 14715.8710241698. The cubic root of 216556860 is about 600.5151686533.

The spelling of 216556860 in words is "two hundred sixteen million, five hundred fifty-six thousand, eight hundred sixty".