27978001 has 4 divisors (see below), whose sum is σ = 28266532. Its totient is φ = 27689472.

The previous prime is 27977981. The next prime is 27978017. The reversal of 27978001 is 10087972.

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 23049601 + 4928400 = 4801^2 + 2220^2 .

It is a cyclic number.

It is not a de Polignac number, because 27978001 - 2¹¹ = 27975953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27978091) 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, 144120 + ... + 144313.

It is an arithmetic number, because the mean of its divisors is an integer number (7066633).

Almost surely, 2^27978001 is an apocalyptic number.

It is an amenable number.

27978001 is a deficient number, since it is larger than the sum of its proper divisors (288531).

27978001 is an equidigital number, since it uses as much as digits as its factorization.

27978001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288530.

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 27978001 is about 5289.4235035588. The cubic root of 27978001 is about 303.5793502550.

The spelling of 27978001 in words is "twenty-seven million, nine hundred seventy-eight thousand, one".