27661728 has 48 divisors (see below), whose sum is σ = 74311776. Its totient is φ = 9004800.

The previous prime is 27661727. The next prime is 27661729. The reversal of 27661728 is 82716672.

It is an interprime number because it is at equal distance from previous prime (27661727) and next prime (27661729).

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (27661721) 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, 778 + ... + 7478.

It is an arithmetic number, because the mean of its divisors is an integer number (1548162).

Almost surely, 2^27661728 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 27661728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37155888).

27661728 is an abundant number, since it is smaller than the sum of its proper divisors (46650048).

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

27661728 is a wasteful number, since it uses less digits than its factorization.

27661728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6757 (or 6749 counting only the distinct ones).

The product of its digits is 56448, while the sum is 39.

The square root of 27661728 is about 5259.4417954760. The cubic root of 27661728 is about 302.4310905578.

The spelling of 27661728 in words is "twenty-seven million, six hundred sixty-one thousand, seven hundred twenty-eight".