664429 has 4 divisors (see below), whose sum is σ = 667584. Its totient is φ = 661276.

The previous prime is 664427. The next prime is 664441. The reversal of 664429 is 924466.

664429 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 664429 - 2¹ = 664427 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a d-powerful number, because it can be written as 6⁵ + 6⁵ + 4 + 4⁸ + 2¹⁹ + 9⁵ .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664429.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1237 + ... + 1690.

It is an arithmetic number, because the mean of its divisors is an integer number (166896).

2⁶⁶⁴⁴²⁹ is an apocalyptic number.

It is an amenable number.

664429 is a deficient number, since it is larger than the sum of its proper divisors (3155).

664429 is a wasteful number, since it uses less digits than its factorization.

664429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3154.

The product of its digits is 10368, while the sum is 31.

The square root of 664429 is about 815.1251437663. The cubic root of 664429 is about 87.2601978212.

The spelling of 664429 in words is "six hundred sixty-four thousand, four hundred twenty-nine".