27878401 has 4 divisors (see below), whose sum is σ = 28558404. Its totient is φ = 27198400.

The previous prime is 27878359. The next prime is 27878423. The reversal of 27878401 is 10487872.

It is a Cunningham number, because it is equal to 5280²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1345600 + 26532801 = 1160^2 + 5151^2 .

It is a cyclic number.

It is not a de Polignac number, because 27878401 - 2¹⁷ = 27747329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27878471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 339940 + ... + 340021.

It is an arithmetic number, because the mean of its divisors is an integer number (7139601).

Almost surely, 2^27878401 is an apocalyptic number.

It is an amenable number.

27878401 is a deficient number, since it is larger than the sum of its proper divisors (680003).

27878401 is an equidigital number, since it uses as much as digits as its factorization.

27878401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680002.

The product of its (nonzero) digits is 25088, while the sum is 37.

The square root of 27878401 is about 5280.0000946970. Note that the first 4 decimals coincide. The cubic root of 27878401 is about 303.2186805219.

The spelling of 27878401 in words is "twenty-seven million, eight hundred seventy-eight thousand, four hundred one".