27381981 has 8 divisors (see below), whose sum is σ = 39828384. Its totient is φ = 16595120.

The previous prime is 27381967. The next prime is 27381997. The reversal of 27381981 is 18918372.

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 27381981 - 2⁷ = 27381853 is a prime.

It is a super-2 number, since 2×27381981² = 1499545766968722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27381901) 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 7 ways as a sum of consecutive naturals, for example, 414846 + ... + 414911.

It is an arithmetic number, because the mean of its divisors is an integer number (4978548).

Almost surely, 2^27381981 is an apocalyptic number.

It is an amenable number.

27381981 is a deficient number, since it is larger than the sum of its proper divisors (12446403).

27381981 is a wasteful number, since it uses less digits than its factorization.

27381981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829771.

The product of its digits is 24192, while the sum is 39.

The square root of 27381981 is about 5232.7794717530. The cubic root of 27381981 is about 301.4081247194.

The spelling of 27381981 in words is "twenty-seven million, three hundred eighty-one thousand, nine hundred eighty-one".