278475979 has 4 divisors (see below), whose sum is σ = 278680176. Its totient is φ = 278271784.

The previous prime is 278475961. The next prime is 278475983. The reversal of 278475979 is 979574872.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 278475979 - 2¹⁹ = 277951691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (278470979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100039 + ... + 102784.

It is an arithmetic number, because the mean of its divisors is an integer number (69670044).

Almost surely, 2^278475979 is an apocalyptic number.

278475979 is a deficient number, since it is larger than the sum of its proper divisors (204197).

278475979 is a wasteful number, since it uses less digits than its factorization.

278475979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204196.

The product of its digits is 8890560, while the sum is 58.

The square root of 278475979 is about 16687.5995577555. The cubic root of 278475979 is about 653.0241558823.

The spelling of 278475979 in words is "two hundred seventy-eight million, four hundred seventy-five thousand, nine hundred seventy-nine".