27430021 has 2 divisors, whose sum is σ = 27430022. Its totient is φ = 27430020.

The previous prime is 27430019. The next prime is 27430043. The reversal of 27430021 is 12003472.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24502500 + 2927521 = 4950^2 + 1711^2 .

It is a cyclic number.

It is not a de Polignac number, because 27430021 - 2¹ = 27430019 is a prime.

Together with 27430019, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27430321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13715010 + 13715011.

It is an arithmetic number, because the mean of its divisors is an integer number (13715011).

Almost surely, 2^27430021 is an apocalyptic number.

It is an amenable number.

27430021 is a deficient number, since it is larger than the sum of its proper divisors (1).

27430021 is an equidigital number, since it uses as much as digits as its factorization.

27430021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 27430021 is about 5237.3677548937. The cubic root of 27430021 is about 301.5842890697.

Adding to 27430021 its reverse (12003472), we get a palindrome (39433493).

The spelling of 27430021 in words is "twenty-seven million, four hundred thirty thousand, twenty-one".