273820021 has 4 divisors (see below), whose sum is σ = 273853132. Its totient is φ = 273786912.

The previous prime is 273820009. The next prime is 273820049. The reversal of 273820021 is 120028372.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 112656996 + 161163025 = 10614^2 + 12695^2 .

It is a cyclic number.

It is not a de Polignac number, because 273820021 - 2⁷ = 273819893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (273820321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7531 + ... + 24583.

It is an arithmetic number, because the mean of its divisors is an integer number (68463283).

Almost surely, 2^273820021 is an apocalyptic number.

It is an amenable number.

273820021 is a deficient number, since it is larger than the sum of its proper divisors (33111).

273820021 is a wasteful number, since it uses less digits than its factorization.

273820021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33110.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 273820021 is about 16547.5079996959. The cubic root of 273820021 is about 649.3642865486.

Adding to 273820021 its reverse (120028372), we get a palindrome (393848393).

The spelling of 273820021 in words is "two hundred seventy-three million, eight hundred twenty thousand, twenty-one".