27981445 has 8 divisors (see below), whose sum is σ = 33606144. Its totient is φ = 22366224.

The previous prime is 27981427. The next prime is 27981449. The reversal of 27981445 is 54418972.

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 27981445 - 2⁵ = 27981413 is a prime.

It is a super-2 number, since 2×27981445² = 1565922528576050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 27981398 and 27981407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27981449) 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, 10212 + ... + 12658.

It is an arithmetic number, because the mean of its divisors is an integer number (4200768).

Almost surely, 2^27981445 is an apocalyptic number.

It is an amenable number.

27981445 is a deficient number, since it is larger than the sum of its proper divisors (5624699).

27981445 is a wasteful number, since it uses less digits than its factorization.

27981445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4739.

The product of its digits is 80640, while the sum is 40.

The square root of 27981445 is about 5289.7490488680. The cubic root of 27981445 is about 303.5918062841.

The spelling of 27981445 in words is "twenty-seven million, nine hundred eighty-one thousand, four hundred forty-five".