280423309 has 2 divisors, whose sum is σ = 280423310. Its totient is φ = 280423308.

The previous prime is 280423267. The next prime is 280423331. The reversal of 280423309 is 903324082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 274830084 + 5593225 = 16578^2 + 2365^2 .

It is a cyclic number.

It is not a de Polignac number, because 280423309 - 2⁹ = 280422797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (280423349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140211654 + 140211655.

It is an arithmetic number, because the mean of its divisors is an integer number (140211655).

Almost surely, 2^280423309 is an apocalyptic number.

It is an amenable number.

280423309 is a deficient number, since it is larger than the sum of its proper divisors (1).

280423309 is an equidigital number, since it uses as much as digits as its factorization.

280423309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 280423309 is about 16745.8445293153. The cubic root of 280423309 is about 654.5427798005.

The spelling of 280423309 in words is "two hundred eighty million, four hundred twenty-three thousand, three hundred nine".