278342399 has 4 divisors (see below), whose sum is σ = 285131280. Its totient is φ = 271553520.

The previous prime is 278342387. The next prime is 278342423. The reversal of 278342399 is 993243872.

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 278342399 - 2⁸ = 278342143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (278342299) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3394379 + ... + 3394460.

It is an arithmetic number, because the mean of its divisors is an integer number (71282820).

Almost surely, 2^278342399 is an apocalyptic number.

278342399 is a deficient number, since it is larger than the sum of its proper divisors (6788881).

278342399 is an equidigital number, since it uses as much as digits as its factorization.

278342399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6788880.

The product of its digits is 653184, while the sum is 47.

The square root of 278342399 is about 16683.5967045479. The cubic root of 278342399 is about 652.9197244714.

The spelling of 278342399 in words is "two hundred seventy-eight million, three hundred forty-two thousand, three hundred ninety-nine".