664206407 has 4 divisors (see below), whose sum is σ = 664328616. Its totient is φ = 664084200.

The previous prime is 664206391. The next prime is 664206409. The reversal of 664206407 is 704602466.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 664206407 - 2⁴ = 664206391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664206409) 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, 52553 + ... + 63954.

It is an arithmetic number, because the mean of its divisors is an integer number (166082154).

Almost surely, 2^664206407 is an apocalyptic number.

664206407 is a deficient number, since it is larger than the sum of its proper divisors (122209).

664206407 is a wasteful number, since it uses less digits than its factorization.

664206407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122208.

The product of its (nonzero) digits is 48384, while the sum is 35.

The square root of 664206407 is about 25772.2022147895. The cubic root of 664206407 is about 872.5045227090.

It can be divided in two parts, 66420 and 6407, that added together give a palindrome (72827).

The spelling of 664206407 in words is "six hundred sixty-four million, two hundred six thousand, four hundred seven".