278180318021 has 2 divisors, whose sum is σ = 278180318022. Its totient is φ = 278180318020.

The previous prime is 278180317993. The next prime is 278180318113. The reversal of 278180318021 is 120813081872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 240820840225 + 37359477796 = 490735^2 + 193286^2 .

It is a cyclic number.

It is not a de Polignac number, because 278180318021 - 2⁶ = 278180317957 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 278180318021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278180318821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139090159010 + 139090159011.

It is an arithmetic number, because the mean of its divisors is an integer number (139090159011).

Almost surely, 2^278180318021 is an apocalyptic number.

It is an amenable number.

278180318021 is a deficient number, since it is larger than the sum of its proper divisors (1).

278180318021 is an equidigital number, since it uses as much as digits as its factorization.

278180318021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43008, while the sum is 41.

Adding to 278180318021 its reverse (120813081872), we get a palindrome (398993399893).

The spelling of 278180318021 in words is "two hundred seventy-eight billion, one hundred eighty million, three hundred eighteen thousand, twenty-one".