278931121 has 16 divisors (see below), whose sum is σ = 340533504. Its totient is φ = 223017984.

The previous prime is 278931113. The next prime is 278931137. The reversal of 278931121 is 121139872.

It is not a de Polignac number, because 278931121 - 2³ = 278931113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (278931181) 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, 3076 + ... + 23818.

It is an arithmetic number, because the mean of its divisors is an integer number (21283344).

Almost surely, 2^278931121 is an apocalyptic number.

It is an amenable number.

278931121 is a deficient number, since it is larger than the sum of its proper divisors (61602383).

278931121 is a wasteful number, since it uses less digits than its factorization.

278931121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20880.

The product of its digits is 6048, while the sum is 34.

The square root of 278931121 is about 16701.2311222856. The cubic root of 278931121 is about 653.3797304675.

The spelling of 278931121 in words is "two hundred seventy-eight million, nine hundred thirty-one thousand, one hundred twenty-one".