278611241 has 2 divisors, whose sum is σ = 278611242. Its totient is φ = 278611240.

The previous prime is 278611211. The next prime is 278611243. The reversal of 278611241 is 142116872.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 254562025 + 24049216 = 15955^2 + 4904^2 .

It is a cyclic number.

It is not a de Polignac number, because 278611241 - 2¹⁴ = 278594857 is a prime.

It is a super-2 number, since 2×278611241² = 155248447223120162, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 278611243, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is equal to p_15154646 and since 278611241 and 15154646 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 278611198 and 278611207.

It is not a weakly prime, because it can be changed into another prime (278611243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139305620 + 139305621.

It is an arithmetic number, because the mean of its divisors is an integer number (139305621).

Almost surely, 2^278611241 is an apocalyptic number.

It is an amenable number.

278611241 is a deficient number, since it is larger than the sum of its proper divisors (1).

278611241 is an equidigital number, since it uses as much as digits as its factorization.

278611241 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5376, while the sum is 32.

The square root of 278611241 is about 16691.6518355734. The cubic root of 278611241 is about 653.1298682390.

The spelling of 278611241 in words is "two hundred seventy-eight million, six hundred eleven thousand, two hundred forty-one".