278961616321 has 12 divisors (see below), whose sum is σ = 294449017408. Its totient is φ = 264242188584.

The previous prime is 278961616303. The next prime is 278961616357. The reversal of 278961616321 is 123616169872.

It is not a de Polignac number, because 278961616321 - 2²⁷ = 278827398593 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (278961616391) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2505405 + ... + 2614378.

Almost surely, 2^278961616321 is an apocalyptic number.

It is an amenable number.

278961616321 is a deficient number, since it is larger than the sum of its proper divisors (15487401087).

278961616321 is a wasteful number, since it uses less digits than its factorization.

278961616321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5119932 (or 5119909 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 52.

The spelling of 278961616321 in words is "two hundred seventy-eight billion, nine hundred sixty-one million, six hundred sixteen thousand, three hundred twenty-one".