278358623 has 2 divisors, whose sum is σ = 278358624. Its totient is φ = 278358622.

The previous prime is 278358601. The next prime is 278358643. The reversal of 278358623 is 326853872.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 278358623 - 2¹⁶ = 278293087 is a prime.

It is a super-2 number, since 2×278358623² = 154967045996912258, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278358643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139179311 + 139179312.

It is an arithmetic number, because the mean of its divisors is an integer number (139179312).

Almost surely, 2^278358623 is an apocalyptic number.

278358623 is a deficient number, since it is larger than the sum of its proper divisors (1).

278358623 is an equidigital number, since it uses as much as digits as its factorization.

278358623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483840, while the sum is 44.

The square root of 278358623 is about 16684.0829235532. The cubic root of 278358623 is about 652.9324100029.

The spelling of 278358623 in words is "two hundred seventy-eight million, three hundred fifty-eight thousand, six hundred twenty-three".