216458240 has 88 divisors (see below), whose sum is σ = 527831232. Its totient is φ = 85155840.

The previous prime is 216458239. The next prime is 216458287. The reversal of 216458240 is 42854612.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 216458197 and 216458206.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 342725 + ... + 343355.

Almost surely, 2^216458240 is an apocalyptic number.

216458240 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 216458240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263915616).

216458240 is an abundant number, since it is smaller than the sum of its proper divisors (311372992).

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

216458240 is an equidigital number, since it uses as much as digits as its factorization.

216458240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 723 (or 705 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 32.

The square root of 216458240 is about 14712.5198385593. The cubic root of 216458240 is about 600.4239966039.

The spelling of 216458240 in words is "two hundred sixteen million, four hundred fifty-eight thousand, two hundred forty".