27979220 has 48 divisors (see below), whose sum is σ = 60858000. Its totient is φ = 10798080.

The previous prime is 27979213. The next prime is 27979249. The reversal of 27979220 is 2297972.

It can be written as a sum of positive squares in 8 ways, for example, as 2617924 + 25361296 = 1618^2 + 5036^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122066 + ... + 122294.

It is an arithmetic number, because the mean of its divisors is an integer number (1267875).

Almost surely, 2^27979220 is an apocalyptic number.

27979220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27979220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30429000).

27979220 is an abundant number, since it is smaller than the sum of its proper divisors (32878780).

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

27979220 is a wasteful number, since it uses less digits than its factorization.

27979220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428 (or 426 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 38.

The square root of 27979220 is about 5289.5387322526. The cubic root of 27979220 is about 303.5837591696.

The spelling of 27979220 in words is "twenty-seven million, nine hundred seventy-nine thousand, two hundred twenty".