278582543581 has 2 divisors, whose sum is σ = 278582543582. Its totient is φ = 278582543580.

The previous prime is 278582543513. The next prime is 278582543609. The reversal of 278582543581 is 185345285872.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 220228411225 + 58354132356 = 469285^2 + 241566^2 .

It is a cyclic number.

It is not a de Polignac number, because 278582543581 - 2⁹ = 278582543069 is a prime.

It is a super-2 number, since 2×278582543581² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278582543881) 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, 139291271790 + 139291271791.

It is an arithmetic number, because the mean of its divisors is an integer number (139291271791).

Almost surely, 2^278582543581 is an apocalyptic number.

It is an amenable number.

278582543581 is a deficient number, since it is larger than the sum of its proper divisors (1).

278582543581 is an equidigital number, since it uses as much as digits as its factorization.

278582543581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21504000, while the sum is 58.

The spelling of 278582543581 in words is "two hundred seventy-eight billion, five hundred eighty-two million, five hundred forty-three thousand, five hundred eighty-one".