27664921 has 2 divisors, whose sum is σ = 27664922. Its totient is φ = 27664920.

The previous prime is 27664909. The next prime is 27664939. The reversal of 27664921 is 12946672.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24651225 + 3013696 = 4965^2 + 1736^2 .

It is a cyclic number.

It is not a de Polignac number, because 27664921 - 2⁹ = 27664409 is a prime.

It is not a weakly prime, because it can be changed into another prime (27664951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13832460 + 13832461.

It is an arithmetic number, because the mean of its divisors is an integer number (13832461).

Almost surely, 2^27664921 is an apocalyptic number.

It is an amenable number.

27664921 is a deficient number, since it is larger than the sum of its proper divisors (1).

27664921 is an equidigital number, since it uses as much as digits as its factorization.

27664921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 37.

The square root of 27664921 is about 5259.7453360405. The cubic root of 27664921 is about 302.4427266749.

The spelling of 27664921 in words is "twenty-seven million, six hundred sixty-four thousand, nine hundred twenty-one".