27721616 has 20 divisors (see below), whose sum is σ = 57842652. Its totient is φ = 12794496.

The previous prime is 27721591. The next prime is 27721619. The reversal of 27721616 is 61612772.

It can be written as a sum of positive squares in 2 ways, for example, as 7507600 + 20214016 = 2740^2 + 4496^2 .

It is not an unprimeable number, because it can be changed into a prime (27721619) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66431 + ... + 66846.

Almost surely, 2^27721616 is an apocalyptic number.

27721616 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

27721616 is an abundant number, since it is smaller than the sum of its proper divisors (30121036).

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

27721616 is a wasteful number, since it uses less digits than its factorization.

27721616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133298 (or 133292 counting only the distinct ones).

The product of its digits is 7056, while the sum is 32.

The square root of 27721616 is about 5265.1320971083. The cubic root of 27721616 is about 302.6491889830.

The spelling of 27721616 in words is "twenty-seven million, seven hundred twenty-one thousand, six hundred sixteen".