278261129 has 2 divisors, whose sum is σ = 278261130. Its totient is φ = 278261128.

The previous prime is 278261059. The next prime is 278261131. The reversal of 278261129 is 921162872.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 203005504 + 75255625 = 14248^2 + 8675^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-278261129 is a prime.

Together with 278261131, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 278261092 and 278261101.

It is not a weakly prime, because it can be changed into another prime (278261029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139130564 + 139130565.

It is an arithmetic number, because the mean of its divisors is an integer number (139130565).

Almost surely, 2^278261129 is an apocalyptic number.

It is an amenable number.

278261129 is a deficient number, since it is larger than the sum of its proper divisors (1).

278261129 is an equidigital number, since it uses as much as digits as its factorization.

278261129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 278261129 is about 16681.1609008486. The cubic root of 278261129 is about 652.8561721088.

The spelling of 278261129 in words is "two hundred seventy-eight million, two hundred sixty-one thousand, one hundred twenty-nine".