27981156 has 72 divisors (see below), whose sum is σ = 79289280. Its totient is φ = 7643328.

The previous prime is 27981131. The next prime is 27981169. The reversal of 27981156 is 65118972.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12490 + ... + 14558.

It is an arithmetic number, because the mean of its divisors is an integer number (1101240).

Almost surely, 2^27981156 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27981156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39644640).

27981156 is an abundant number, since it is smaller than the sum of its proper divisors (51308124).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27981156 is a wasteful number, since it uses less digits than its factorization.

27981156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2113 (or 2104 counting only the distinct ones).

The product of its digits is 30240, while the sum is 39.

The square root of 27981156 is about 5289.7217318116. The cubic root of 27981156 is about 303.5907610875.

The spelling of 27981156 in words is "twenty-seven million, nine hundred eighty-one thousand, one hundred fifty-six".