27998291 has 4 divisors (see below), whose sum is σ = 29215632. Its totient is φ = 26780952.

The previous prime is 27998287. The next prime is 27998359. The reversal of 27998291 is 19289972.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 27998291 - 2² = 27998287 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27998251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 608636 + ... + 608681.

It is an arithmetic number, because the mean of its divisors is an integer number (7303908).

Almost surely, 2^27998291 is an apocalyptic number.

27998291 is a deficient number, since it is larger than the sum of its proper divisors (1217341).

27998291 is a wasteful number, since it uses less digits than its factorization.

27998291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1217340.

The product of its digits is 163296, while the sum is 47.

The square root of 27998291 is about 5291.3411343439. The cubic root of 27998291 is about 303.6527190493.

It can be divided in two parts, 27998 and 291, that multiplied together give a palindrome (8147418).

The spelling of 27998291 in words is "twenty-seven million, nine hundred ninety-eight thousand, two hundred ninety-one".