278216345 has 16 divisors (see below), whose sum is σ = 371086272. Its totient is φ = 198519360.

The previous prime is 278216327. The next prime is 278216369. The reversal of 278216345 is 543612872.

It is a happy number.

It is not a de Polignac number, because 278216345 - 2²² = 274022041 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 278216299 and 278216308.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44807 + ... + 50636.

It is an arithmetic number, because the mean of its divisors is an integer number (23192892).

Almost surely, 2^278216345 is an apocalyptic number.

It is an amenable number.

278216345 is a deficient number, since it is larger than the sum of its proper divisors (92869927).

278216345 is a wasteful number, since it uses less digits than its factorization.

278216345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95512.

The product of its digits is 80640, while the sum is 38.

The square root of 278216345 is about 16679.8184942163. The cubic root of 278216345 is about 652.8211461608.

The spelling of 278216345 in words is "two hundred seventy-eight million, two hundred sixteen thousand, three hundred forty-five".