278332643 has 2 divisors, whose sum is σ = 278332644. Its totient is φ = 278332642.

The previous prime is 278332597. The next prime is 278332667. The reversal of 278332643 is 346233872.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-278332643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 278332597 and 278332606.

It is not a weakly prime, because it can be changed into another prime (278332693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139166321 + 139166322.

It is an arithmetic number, because the mean of its divisors is an integer number (139166322).

Almost surely, 2^278332643 is an apocalyptic number.

278332643 is a deficient number, since it is larger than the sum of its proper divisors (1).

278332643 is an equidigital number, since it uses as much as digits as its factorization.

278332643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 38.

The square root of 278332643 is about 16683.3043189891. The cubic root of 278332643 is about 652.9120960262.

The spelling of 278332643 in words is "two hundred seventy-eight million, three hundred thirty-two thousand, six hundred forty-three".