278344428 has 12 divisors (see below), whose sum is σ = 649470360. Its totient is φ = 92781472.

The previous prime is 278344427. The next prime is 278344441. The reversal of 278344428 is 824443872.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 278344428.

It is not an unprimeable number, because it can be changed into a prime (278344427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11597673 + ... + 11597696.

It is an arithmetic number, because the mean of its divisors is an integer number (54122530).

Almost surely, 2^278344428 is an apocalyptic number.

It is an amenable number.

278344428 is an abundant number, since it is smaller than the sum of its proper divisors (371125932).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

278344428 is a wasteful number, since it uses less digits than its factorization.

278344428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23195376 (or 23195374 counting only the distinct ones).

The product of its digits is 344064, while the sum is 42.

The square root of 278344428 is about 16683.6575126679. The cubic root of 278344428 is about 652.9213109717.

The spelling of 278344428 in words is "two hundred seventy-eight million, three hundred forty-four thousand, four hundred twenty-eight".