278230681 has 2 divisors, whose sum is σ = 278230682. Its totient is φ = 278230680.

The previous prime is 278230679. The next prime is 278230781. The reversal of 278230681 is 186032872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 278222400 + 8281 = 16680^2 + 91^2 .

It is a cyclic number.

It is not a de Polignac number, because 278230681 - 2¹ = 278230679 is a prime.

It is a super-2 number, since 2×278230681² = 154824623699447522, which contains 22 as substring.

Together with 278230679, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 278230681.

It is not a weakly prime, because it can be changed into another prime (278230781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139115340 + 139115341.

It is an arithmetic number, because the mean of its divisors is an integer number (139115341).

Almost surely, 2^278230681 is an apocalyptic number.

It is an amenable number.

278230681 is a deficient number, since it is larger than the sum of its proper divisors (1).

278230681 is an equidigital number, since it uses as much as digits as its factorization.

278230681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 278230681 is about 16680.2482295678. The cubic root of 278230681 is about 652.8323588776.

The spelling of 278230681 in words is "two hundred seventy-eight million, two hundred thirty thousand, six hundred eighty-one".