278535240 has 64 divisors (see below), whose sum is σ = 928454400. Its totient is φ = 74275776.

The previous prime is 278535239. The next prime is 278535241. The reversal of 278535240 is 42535872.

It is an interprime number because it is at equal distance from previous prime (278535239) and next prime (278535241).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 278535195 and 278535204.

It is not an unprimeable number, because it can be changed into a prime (278535241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127872 + ... + 130031.

It is an arithmetic number, because the mean of its divisors is an integer number (14507100).

Almost surely, 2^278535240 is an apocalyptic number.

278535240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

278535240 is an abundant number, since it is smaller than the sum of its proper divisors (649919160).

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

278535240 is a wasteful number, since it uses less digits than its factorization.

278535240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257923 (or 257913 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The square root of 278535240 is about 16689.3750631951. The cubic root of 278535240 is about 653.0704748023.

It can be divided in two parts, 2785 and 35240, that added together give a square (38025 = 195²).

The spelling of 278535240 in words is "two hundred seventy-eight million, five hundred thirty-five thousand, two hundred forty".