278487979 has 32 divisors (see below), whose sum is σ = 367865856. Its totient is φ = 204383520.

The previous prime is 278487977. The next prime is 278488037. The reversal of 278487979 is 979784872.

It is not a de Polignac number, because 278487979 - 2¹ = 278487977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (278487971) 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, 117484 + ... + 119830.

It is an arithmetic number, because the mean of its divisors is an integer number (11495808).

Almost surely, 2^278487979 is an apocalyptic number.

278487979 is a deficient number, since it is larger than the sum of its proper divisors (89377877).

278487979 is a wasteful number, since it uses less digits than its factorization.

278487979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2455.

The product of its digits is 14224896, while the sum is 61.

The square root of 278487979 is about 16687.9591022989. The cubic root of 278487979 is about 653.0335357187.

The spelling of 278487979 in words is "two hundred seventy-eight million, four hundred eighty-seven thousand, nine hundred seventy-nine".