27904640 has 64 divisors (see below), whose sum is σ = 67932000. Its totient is φ = 10957824.

The previous prime is 27904631. The next prime is 27904663. The reversal of 27904640 is 4640972.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 27904597 and 27904606.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37391 + ... + 38129.

Almost surely, 2^27904640 is an apocalyptic number.

27904640 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 27904640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33966000).

27904640 is an abundant number, since it is smaller than the sum of its proper divisors (40027360).

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

27904640 is an equidigital number, since it uses as much as digits as its factorization.

27904640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 817 (or 805 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 27904640 is about 5282.4842640561. The cubic root of 27904640 is about 303.3137799523.

The spelling of 27904640 in words is "twenty-seven million, nine hundred four thousand, six hundred forty".