280472821 has 2 divisors, whose sum is σ = 280472822. Its totient is φ = 280472820.

The previous prime is 280472809. The next prime is 280472867. The reversal of 280472821 is 128274082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 266146596 + 14326225 = 16314^2 + 3785^2 .

It is a cyclic number.

It is not a de Polignac number, because 280472821 - 2¹⁷ = 280341749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (280470821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140236410 + 140236411.

It is an arithmetic number, because the mean of its divisors is an integer number (140236411).

Almost surely, 2^280472821 is an apocalyptic number.

It is an amenable number.

280472821 is a deficient number, since it is larger than the sum of its proper divisors (1).

280472821 is an equidigital number, since it uses as much as digits as its factorization.

280472821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14336, while the sum is 34.

The square root of 280472821 is about 16747.3228009733. The cubic root of 280472821 is about 654.5812999163.

It can be divided in two parts, 2804 and 72821, that added together give a square (75625 = 275²).

The spelling of 280472821 in words is "two hundred eighty million, four hundred seventy-two thousand, eight hundred twenty-one".