273821 has 2 divisors, whose sum is σ = 273822. Its totient is φ = 273820.

The previous prime is 273803. The next prime is 273827. The reversal of 273821 is 128372.

273821 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151321 + 122500 = 389^2 + 350^2 .

It is a cyclic number.

It is not a de Polignac number, because 273821 - 2¹⁴ = 257437 is a prime.

It is a Sophie Germain prime.

It is an Ulam number.

It is a Curzon number.

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 273821.

It is not a weakly prime, because it can be changed into another prime (273827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 136910 + 136911.

It is an arithmetic number, because the mean of its divisors is an integer number (136911).

2²⁷³⁸²¹ is an apocalyptic number.

It is an amenable number.

273821 is a deficient number, since it is larger than the sum of its proper divisors (1).

273821 is an equidigital number, since it uses as much as digits as its factorization.

273821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 672, while the sum is 23.

The square root of 273821 is about 523.2790842371. The cubic root of 273821 is about 64.9365060447.

The spelling of 273821 in words is "two hundred seventy-three thousand, eight hundred twenty-one".