278678642 has 16 divisors (see below), whose sum is σ = 461516832. Its totient is φ = 125145120.

The previous prime is 278678639. The next prime is 278678689. The reversal of 278678642 is 246876872.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74483 + ... + 78134.

It is an arithmetic number, because the mean of its divisors is an integer number (28844802).

Almost surely, 2^278678642 is an apocalyptic number.

278678642 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

278678642 is a deficient number, since it is larger than the sum of its proper divisors (182838190).

278678642 is a wasteful number, since it uses less digits than its factorization.

278678642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152713.

The product of its digits is 1806336, while the sum is 50.

The square root of 278678642 is about 16693.6707167717. The cubic root of 278678642 is about 653.1825318917.

The spelling of 278678642 in words is "two hundred seventy-eight million, six hundred seventy-eight thousand, six hundred forty-two".