280243643 has 2 divisors, whose sum is σ = 280243644. Its totient is φ = 280243642.

The previous prime is 280243637. The next prime is 280243679. The reversal of 280243643 is 346342082.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-280243643 is a prime.

It is a super-2 number, since 2×280243643² = 157072998883822898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (280243633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140121821 + 140121822.

It is an arithmetic number, because the mean of its divisors is an integer number (140121822).

Almost surely, 2^280243643 is an apocalyptic number.

280243643 is a deficient number, since it is larger than the sum of its proper divisors (1).

280243643 is an equidigital number, since it uses as much as digits as its factorization.

280243643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 32.

The square root of 280243643 is about 16740.4791747429. The cubic root of 280243643 is about 654.4029623610.

The spelling of 280243643 in words is "two hundred eighty million, two hundred forty-three thousand, six hundred forty-three".