278978868 has 144 divisors (see below), whose sum is σ = 849838080. Its totient is φ = 75442752.

The previous prime is 278978831. The next prime is 278978879. The reversal of 278978868 is 868879872.

278978868 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×278978868² = 155658417581122848, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 735903 + ... + 736281.

Almost surely, 2^278978868 is an apocalyptic number.

278978868 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 278978868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (424919040).

278978868 is an abundant number, since it is smaller than the sum of its proper divisors (570859212).

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

278978868 is a wasteful number, since it uses less digits than its factorization.

278978868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546 (or 541 counting only the distinct ones).

The product of its digits is 21676032, while the sum is 63.

The square root of 278978868 is about 16702.6605066379. The cubic root of 278978868 is about 653.4170098527.

The spelling of 278978868 in words is "two hundred seventy-eight million, nine hundred seventy-eight thousand, eight hundred sixty-eight".