278773243 has 4 divisors (see below), whose sum is σ = 318598000. Its totient is φ = 238948488.

The previous prime is 278773223. The next prime is 278773273. The reversal of 278773243 is 342377872.

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 278773243 - 2²⁵ = 245218811 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 278773243.

It is not an unprimeable number, because it can be changed into a prime (278773213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19912368 + ... + 19912381.

It is an arithmetic number, because the mean of its divisors is an integer number (79649500).

Almost surely, 2^278773243 is an apocalyptic number.

278773243 is a deficient number, since it is larger than the sum of its proper divisors (39824757).

278773243 is an equidigital number, since it uses as much as digits as its factorization.

278773243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39824756.

The product of its digits is 395136, while the sum is 43.

The square root of 278773243 is about 16696.5039154908. The cubic root of 278773243 is about 653.2564338953.

The spelling of 278773243 in words is "two hundred seventy-eight million, seven hundred seventy-three thousand, two hundred forty-three".