27999880 has 64 divisors (see below), whose sum is σ = 65640960. Its totient is φ = 10741248.

The previous prime is 27999869. The next prime is 27999883. The reversal of 27999880 is 8899972.

It is not an unprimeable number, because it can be changed into a prime (27999883) 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 15 ways as a sum of consecutive naturals, for example, 125449 + ... + 125671.

It is an arithmetic number, because the mean of its divisors is an integer number (1025640).

Almost surely, 2^27999880 is an apocalyptic number.

27999880 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 27999880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32820480).

27999880 is an abundant number, since it is smaller than the sum of its proper divisors (37641080).

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

27999880 is a wasteful number, since it uses less digits than its factorization.

27999880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350 (or 346 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 52.

The square root of 27999880 is about 5291.4912831828. The cubic root of 27999880 is about 303.6584633885.

The spelling of 27999880 in words is "twenty-seven million, nine hundred ninety-nine thousand, eight hundred eighty".