278845247 has 2 divisors, whose sum is σ = 278845248. Its totient is φ = 278845246.

The previous prime is 278845201. The next prime is 278845249. The reversal of 278845247 is 742548872.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 278845247 - 2⁶ = 278845183 is a prime.

Together with 278845249, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278845249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139422623 + 139422624.

It is an arithmetic number, because the mean of its divisors is an integer number (139422624).

Almost surely, 2^278845247 is an apocalyptic number.

278845247 is a deficient number, since it is larger than the sum of its proper divisors (1).

278845247 is an equidigital number, since it uses as much as digits as its factorization.

278845247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1003520, while the sum is 47.

The square root of 278845247 is about 16698.6600360628. The cubic root of 278845247 is about 653.3126719888.

The spelling of 278845247 in words is "two hundred seventy-eight million, eight hundred forty-five thousand, two hundred forty-seven".