278977842 has 144 divisors (see below), whose sum is σ = 731989440. Its totient is φ = 76253760.

The previous prime is 278977841. The next prime is 278977877. The reversal of 278977842 is 248779872.

It is not an unprimeable number, because it can be changed into a prime (278977841) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1670443 + ... + 1670609.

It is an arithmetic number, because the mean of its divisors is an integer number (5083260).

Almost surely, 2^278977842 is an apocalyptic number.

278977842 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 278977842, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (365994720).

278977842 is an abundant number, since it is smaller than the sum of its proper divisors (453011598).

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

278977842 is a wasteful number, since it uses less digits than its factorization.

278977842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 255 counting only the distinct ones).

The product of its digits is 3161088, while the sum is 54.

The square root of 278977842 is about 16702.6297929398. The cubic root of 278977842 is about 653.4162088283.

The spelling of 278977842 in words is "two hundred seventy-eight million, nine hundred seventy-seven thousand, eight hundred forty-two".