278787428 has 12 divisors (see below), whose sum is σ = 488167680. Its totient is φ = 139310952.

The previous prime is 278787401. The next prime is 278787451. The reversal of 278787428 is 824787872.

It is a self number, because there is not a number n which added to its sum of digits gives 278787428.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12776 + ... + 26847.

It is an arithmetic number, because the mean of its divisors is an integer number (40680640).

Almost surely, 2^278787428 is an apocalyptic number.

It is an amenable number.

278787428 is a deficient number, since it is larger than the sum of its proper divisors (209380252).

278787428 is a wasteful number, since it uses less digits than its factorization.

278787428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41386 (or 41384 counting only the distinct ones).

The product of its digits is 2809856, while the sum is 53.

The square root of 278787428 is about 16696.9286996142. The cubic root of 278787428 is about 653.2675137312.

The spelling of 278787428 in words is "two hundred seventy-eight million, seven hundred eighty-seven thousand, four hundred twenty-eight".