27730638 has 48 divisors (see below), whose sum is σ = 68520816. Its totient is φ = 8029440.

The previous prime is 27730631. The next prime is 27730667. The reversal of 27730638 is 83603772.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27730631) 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 23 ways as a sum of consecutive naturals, for example, 493 + ... + 7463.

It is an arithmetic number, because the mean of its divisors is an integer number (1427517).

Almost surely, 2^27730638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27730638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34260408).

27730638 is an abundant number, since it is smaller than the sum of its proper divisors (40790178).

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

27730638 is a wasteful number, since it uses less digits than its factorization.

27730638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7009 (or 7006 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 36.

The square root of 27730638 is about 5265.9887960382. The cubic root of 27730638 is about 302.6820178150.

The spelling of 27730638 in words is "twenty-seven million, seven hundred thirty thousand, six hundred thirty-eight".