278434997 has 2 divisors, whose sum is σ = 278434998. Its totient is φ = 278434996.

The previous prime is 278434991. The next prime is 278434999. The reversal of 278434997 is 799434872.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 276689956 + 1745041 = 16634^2 + 1321^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-278434997 is a prime.

Together with 278434999, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (278434991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 139217498 + 139217499.

It is an arithmetic number, because the mean of its divisors is an integer number (139217499).

Almost surely, 2^278434997 is an apocalyptic number.

It is an amenable number.

278434997 is a deficient number, since it is larger than the sum of its proper divisors (1).

278434997 is an equidigital number, since it uses as much as digits as its factorization.

278434997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3048192, while the sum is 53.

The square root of 278434997 is about 16686.3715948075. The cubic root of 278434997 is about 652.9921201463.

The spelling of 278434997 in words is "two hundred seventy-eight million, four hundred thirty-four thousand, nine hundred ninety-seven".