664427 has 2 divisors, whose sum is σ = 664428. Its totient is φ = 664426.

The previous prime is 664421. The next prime is 664441. The reversal of 664427 is 724466.

664427 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664427 - 2¹⁶ = 598891 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 664427.

It is not a weakly prime, because it can be changed into another prime (664421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332213 + 332214.

It is an arithmetic number, because the mean of its divisors is an integer number (332214).

2⁶⁶⁴⁴²⁷ is an apocalyptic number.

664427 is a deficient number, since it is larger than the sum of its proper divisors (1).

664427 is an equidigital number, since it uses as much as digits as its factorization.

664427 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 29.

The square root of 664427 is about 815.1239169599. The cubic root of 664427 is about 87.2601102670.

The spelling of 664427 in words is "six hundred sixty-four thousand, four hundred twenty-seven".