27997321 has 4 divisors (see below), whose sum is σ = 30542544. Its totient is φ = 25452100.

The previous prime is 27997313. The next prime is 27997327. The reversal of 27997321 is 12379972.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27997321 - 2³ = 27997313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27997327) 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, 1272595 + ... + 1272616.

It is an arithmetic number, because the mean of its divisors is an integer number (7635636).

Almost surely, 2^27997321 is an apocalyptic number.

It is an amenable number.

27997321 is a deficient number, since it is larger than the sum of its proper divisors (2545223).

27997321 is a wasteful number, since it uses less digits than its factorization.

27997321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2545222.

The product of its digits is 47628, while the sum is 40.

The square root of 27997321 is about 5291.2494743680. The cubic root of 27997321 is about 303.6492123289.

The spelling of 27997321 in words is "twenty-seven million, nine hundred ninety-seven thousand, three hundred twenty-one".