280021279 has 2 divisors, whose sum is σ = 280021280. Its totient is φ = 280021278.

The previous prime is 280021237. The next prime is 280021283. The reversal of 280021279 is 972120082.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 280021279 - 2⁷ = 280021151 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 280021279.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (280021219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140010639 + 140010640.

It is an arithmetic number, because the mean of its divisors is an integer number (140010640).

Almost surely, 2^280021279 is an apocalyptic number.

280021279 is a deficient number, since it is larger than the sum of its proper divisors (1).

280021279 is an equidigital number, since it uses as much as digits as its factorization.

280021279 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 280021279 is about 16733.8363503412. The cubic root of 280021279 is about 654.2298342417.

The spelling of 280021279 in words is "two hundred eighty million, twenty-one thousand, two hundred seventy-nine".