216858780 has 72 divisors (see below), whose sum is σ = 692437200. Its totient is φ = 54784512.

The previous prime is 216858767. The next prime is 216858791. The reversal of 216858780 is 87858612.

216858780 is a `hidden beast` number, since 2 + 1 + 68 + 587 + 8 + 0 = 666.

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 23 ways as a sum of consecutive naturals, for example, 28285 + ... + 35124.

Almost surely, 2^216858780 is an apocalyptic number.

216858780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216858780 is an abundant number, since it is smaller than the sum of its proper divisors (475578420).

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

216858780 is a wasteful number, since it uses less digits than its factorization.

216858780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63443 (or 63438 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 45.

The square root of 216858780 is about 14726.1257634179. The cubic root of 216858780 is about 600.7941151715.

The spelling of 216858780 in words is "two hundred sixteen million, eight hundred fifty-eight thousand, seven hundred eighty".