27661530 has 64 divisors (see below), whose sum is σ = 75277440. Its totient is φ = 6448896.

The previous prime is 27661523. The next prime is 27661531. The reversal of 27661530 is 3516672.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (27661531) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5544 + ... + 9276.

It is an arithmetic number, because the mean of its divisors is an integer number (1176210).

Almost surely, 2^27661530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27661530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37638720).

27661530 is an abundant number, since it is smaller than the sum of its proper divisors (47615910).

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

27661530 is a wasteful number, since it uses less digits than its factorization.

27661530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3775.

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 27661530 is about 5259.4229721520. The cubic root of 27661530 is about 302.4303689651.

The spelling of 27661530 in words is "twenty-seven million, six hundred sixty-one thousand, five hundred thirty".