280403993 has 2 divisors, whose sum is σ = 280403994. Its totient is φ = 280403992.

The previous prime is 280403969. The next prime is 280404029. The reversal of 280403993 is 399304082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 141800464 + 138603529 = 11908^2 + 11773^2 .

It is a cyclic number.

It is not a de Polignac number, because 280403993 - 2¹² = 280399897 is a prime.

It is not a weakly prime, because it can be changed into another prime (280403923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140201996 + 140201997.

It is an arithmetic number, because the mean of its divisors is an integer number (140201997).

Almost surely, 2^280403993 is an apocalyptic number.

It is an amenable number.

280403993 is a deficient number, since it is larger than the sum of its proper divisors (1).

280403993 is an equidigital number, since it uses as much as digits as its factorization.

280403993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 280403993 is about 16745.2677792862. The cubic root of 280403993 is about 654.5277508089.

The spelling of 280403993 in words is "two hundred eighty million, four hundred three thousand, nine hundred ninety-three".