278612649187 has 2 divisors, whose sum is σ = 278612649188. Its totient is φ = 278612649186.

The previous prime is 278612649173. The next prime is 278612649191. The reversal of 278612649187 is 781946216872.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-278612649187 is a prime.

It is not a weakly prime, because it can be changed into another prime (278612644187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139306324593 + 139306324594.

It is an arithmetic number, because the mean of its divisors is an integer number (139306324594).

Almost surely, 2^278612649187 is an apocalyptic number.

278612649187 is a deficient number, since it is larger than the sum of its proper divisors (1).

278612649187 is an equidigital number, since it uses as much as digits as its factorization.

278612649187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16257024, while the sum is 61.

The spelling of 278612649187 in words is "two hundred seventy-eight billion, six hundred twelve million, six hundred forty-nine thousand, one hundred eighty-seven".