278547979 has 2 divisors, whose sum is σ = 278547980. Its totient is φ = 278547978.

The previous prime is 278547977. The next prime is 278548033. The reversal of 278547979 is 979745872.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 278547979 - 2¹ = 278547977 is a prime.

Together with 278547977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (278547977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139273989 + 139273990.

It is an arithmetic number, because the mean of its divisors is an integer number (139273990).

Almost surely, 2^278547979 is an apocalyptic number.

278547979 is a deficient number, since it is larger than the sum of its proper divisors (1).

278547979 is an equidigital number, since it uses as much as digits as its factorization.

278547979 is an evil number, because the sum of its binary digits is even.

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

The square root of 278547979 is about 16689.7567088319. The cubic root of 278547979 is about 653.0804308590.

The spelling of 278547979 in words is "two hundred seventy-eight million, five hundred forty-seven thousand, nine hundred seventy-nine".