278942481749 has 2 divisors, whose sum is σ = 278942481750. Its totient is φ = 278942481748.

The previous prime is 278942481739. The next prime is 278942481791. The reversal of 278942481749 is 947184249872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 244376979025 + 34565502724 = 494345^2 + 185918^2 .

It is a cyclic number.

It is not a de Polignac number, because 278942481749 - 2¹⁶ = 278942416213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278942481739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139471240874 + 139471240875.

It is an arithmetic number, because the mean of its divisors is an integer number (139471240875).

Almost surely, 2^278942481749 is an apocalyptic number.

It is an amenable number.

278942481749 is a deficient number, since it is larger than the sum of its proper divisors (1).

278942481749 is an equidigital number, since it uses as much as digits as its factorization.

278942481749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 65028096, while the sum is 65.

The spelling of 278942481749 in words is "two hundred seventy-eight billion, nine hundred forty-two million, four hundred eighty-one thousand, seven hundred forty-nine".