278287940 has 48 divisors (see below), whose sum is σ = 682117632. Its totient is φ = 93380736.

The previous prime is 278287939. The next prime is 278287949. The reversal of 278287940 is 49782872.

It is a happy number.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is not an unprimeable number, because it can be changed into a prime (278287949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14567 + ... + 27726.

It is an arithmetic number, because the mean of its divisors is an integer number (14210784).

Almost surely, 2^278287940 is an apocalyptic number.

278287940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

278287940 is an abundant number, since it is smaller than the sum of its proper divisors (403829692).

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

278287940 is a wasteful number, since it uses less digits than its factorization.

278287940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42356 (or 42354 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 47.

The square root of 278287940 is about 16681.9645126106. The cubic root of 278287940 is about 652.8771394219.

The spelling of 278287940 in words is "two hundred seventy-eight million, two hundred eighty-seven thousand, nine hundred forty".