27280721 has 8 divisors (see below), whose sum is σ = 29535744. Its totient is φ = 25048080.

The previous prime is 27280697. The next prime is 27280723. The reversal of 27280721 is 12708272.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 27280721 - 2¹⁰ = 27279697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (27280723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3011 + ... + 7976.

It is an arithmetic number, because the mean of its divisors is an integer number (3691968).

Almost surely, 2^27280721 is an apocalyptic number.

It is an amenable number.

27280721 is a deficient number, since it is larger than the sum of its proper divisors (2255023).

27280721 is a wasteful number, since it uses less digits than its factorization.

27280721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11191.

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 27280721 is about 5223.0949637164. The cubic root of 27280721 is about 301.0361247725.

Adding to 27280721 its reverse (12708272), we get a palindrome (39988993).

The spelling of 27280721 in words is "twenty-seven million, two hundred eighty thousand, seven hundred twenty-one".