280121 has 2 divisors, whose sum is σ = 280122. Its totient is φ = 280120.

The previous prime is 280103. The next prime is 280129. The reversal of 280121 is 121082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 212521 + 67600 = 461^2 + 260^2 .

It is a cyclic number.

It is not a de Polignac number, because 280121 - 2¹⁴ = 263737 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 280096 and 280105.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 280121.

It is not a weakly prime, because it can be changed into another prime (280129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140060 + 140061.

It is an arithmetic number, because the mean of its divisors is an integer number (140061).

2²⁸⁰¹²¹ is an apocalyptic number.

It is an amenable number.

280121 is a deficient number, since it is larger than the sum of its proper divisors (1).

280121 is an equidigital number, since it uses as much as digits as its factorization.

280121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 280121 is about 529.2645841165. The cubic root of 280121 is about 65.4307486329.

The spelling of 280121 in words is "two hundred eighty thousand, one hundred twenty-one".