216306280 has 32 divisors (see below), whose sum is σ = 489969000. Its totient is φ = 85939456.

The previous prime is 216306263. The next prime is 216306287. The reversal of 216306280 is 82603612.

It can be written as a sum of positive squares in 4 ways, for example, as 59505796 + 156800484 = 7714^2 + 12522^2 .

It is not an unprimeable number, because it can be changed into a prime (216306287) 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, 12187 + ... + 24106.

Almost surely, 2^216306280 is an apocalyptic number.

216306280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216306280 is an abundant number, since it is smaller than the sum of its proper divisors (273662720).

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

216306280 is a wasteful number, since it uses less digits than its factorization.

216306280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36453 (or 36449 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 216306280 is about 14707.3546227729. The cubic root of 216306280 is about 600.2834586568.

Adding to 216306280 its reverse (82603612), we get a palindrome (298909892).

The spelling of 216306280 in words is "two hundred sixteen million, three hundred six thousand, two hundred eighty".