27205921 has 2 divisors, whose sum is σ = 27205922. Its totient is φ = 27205920.

The previous prime is 27205909. The next prime is 27205931. The reversal of 27205921 is 12950272.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20575296 + 6630625 = 4536^2 + 2575^2 .

It is a cyclic number.

It is not a de Polignac number, because 27205921 - 2⁵ = 27205889 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27205921.

It is not a weakly prime, because it can be changed into another prime (27205901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13602960 + 13602961.

It is an arithmetic number, because the mean of its divisors is an integer number (13602961).

Almost surely, 2^27205921 is an apocalyptic number.

It is an amenable number.

27205921 is a deficient number, since it is larger than the sum of its proper divisors (1).

27205921 is an equidigital number, since it uses as much as digits as its factorization.

27205921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 27205921 is about 5215.9295432358. The cubic root of 27205921 is about 300.7607396570.

The spelling of 27205921 in words is "twenty-seven million, two hundred five thousand, nine hundred twenty-one".