278397378 has 64 divisors (see below), whose sum is σ = 709827840. Its totient is φ = 79228800.

The previous prime is 278397377. The next prime is 278397397. The reversal of 278397378 is 873793872.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (278397377) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 104908 + ... + 107528.

It is an arithmetic number, because the mean of its divisors is an integer number (11091060).

Almost surely, 2^278397378 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 278397378, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (354913920).

278397378 is an abundant number, since it is smaller than the sum of its proper divisors (431430462).

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

278397378 is a wasteful number, since it uses less digits than its factorization.

278397378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2920 (or 2914 counting only the distinct ones).

The product of its digits is 3556224, while the sum is 54.

The square root of 278397378 is about 16685.2443194578. The cubic root of 278397378 is about 652.9627105088.

The spelling of 278397378 in words is "two hundred seventy-eight million, three hundred ninety-seven thousand, three hundred seventy-eight".