27920909 has 2 divisors, whose sum is σ = 27920910. Its totient is φ = 27920908.

The previous prime is 27920887. The next prime is 27920929. The reversal of 27920909 is 90902972.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17455684 + 10465225 = 4178^2 + 3235^2 .

It is a cyclic number.

It is not a de Polignac number, because 27920909 - 2¹² = 27916813 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27920929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13960454 + 13960455.

It is an arithmetic number, because the mean of its divisors is an integer number (13960455).

Almost surely, 2^27920909 is an apocalyptic number.

It is an amenable number.

27920909 is a deficient number, since it is larger than the sum of its proper divisors (1).

27920909 is an equidigital number, since it uses as much as digits as its factorization.

27920909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20412, while the sum is 38.

The square root of 27920909 is about 5284.0239401426. The cubic root of 27920909 is about 303.3727146336.

The spelling of 27920909 in words is "twenty-seven million, nine hundred twenty thousand, nine hundred nine".