278204231 has 2 divisors, whose sum is σ = 278204232. Its totient is φ = 278204230.

The previous prime is 278204219. The next prime is 278204237. The reversal of 278204231 is 132402872.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-278204231 is a prime.

It is a super-2 number, since 2×278204231² = 154795188292602722, which contains 22 as substring.

It is equal to p_15133763 and since 278204231 and 15133763 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 = 278204194 and 278204203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278204237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139102115 + 139102116.

It is an arithmetic number, because the mean of its divisors is an integer number (139102116).

Almost surely, 2^278204231 is an apocalyptic number.

278204231 is a deficient number, since it is larger than the sum of its proper divisors (1).

278204231 is an equidigital number, since it uses as much as digits as its factorization.

278204231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 278204231 is about 16679.4553568155. The cubic root of 278204231 is about 652.8116710523.

The spelling of 278204231 in words is "two hundred seventy-eight million, two hundred four thousand, two hundred thirty-one".