216897660 has 144 divisors (see below), whose sum is σ = 761779200. Its totient is φ = 48926592.

The previous prime is 216897647. The next prime is 216897671. The reversal of 216897660 is 66798612.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 98451 + ... + 100629.

Almost surely, 2^216897660 is an apocalyptic number.

216897660 is a gapful number since it is divisible by the number (20) 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 216897660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (380889600).

216897660 is an abundant number, since it is smaller than the sum of its proper divisors (544881540).

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

216897660 is a wasteful number, since it uses less digits than its factorization.

216897660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2280 (or 2275 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 216897660 is about 14727.4458070638. The cubic root of 216897660 is about 600.8300179210.

The spelling of 216897660 in words is "two hundred sixteen million, eight hundred ninety-seven thousand, six hundred sixty".