27781272 has 64 divisors (see below), whose sum is σ = 79077600. Its totient is φ = 9031680.

The previous prime is 27781267. The next prime is 27781279. The reversal of 27781272 is 27218772.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27781279) 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 15 ways as a sum of consecutive naturals, for example, 7288 + ... + 10424.

Almost surely, 2^27781272 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 27781272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39538800).

27781272 is an abundant number, since it is smaller than the sum of its proper divisors (51296328).

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

27781272 is a wasteful number, since it uses less digits than its factorization.

27781272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3193 (or 3183 counting only the distinct ones).

The product of its digits is 21952, while the sum is 36.

The square root of 27781272 is about 5270.7942475494. The cubic root of 27781272 is about 302.8661304526.

Subtracting from 27781272 its reverse (27218772), we obtain a square (562500 = 750²).

The spelling of 27781272 in words is "twenty-seven million, seven hundred eighty-one thousand, two hundred seventy-two".