664445403 has 16 divisors (see below), whose sum is σ = 984871200. Its totient is φ = 442735200.

The previous prime is 664445393. The next prime is 664445407. The reversal of 664445403 is 304544466.

664445403 is a `hidden beast` number, since 6 + 644 + 4 + 5 + 4 + 0 + 3 = 666.

It is not a de Polignac number, because 664445403 - 2⁶ = 664445339 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (664445407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59353 + ... + 69653.

It is an arithmetic number, because the mean of its divisors is an integer number (61554450).

Almost surely, 2^664445403 is an apocalyptic number.

664445403 is a deficient number, since it is larger than the sum of its proper divisors (320425797).

664445403 is a wasteful number, since it uses less digits than its factorization.

664445403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12699 (or 12693 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 36.

The square root of 664445403 is about 25776.8384989316. The cubic root of 664445403 is about 872.6091588999.

Adding to 664445403 its reverse (304544466), we get a palindrome (968989869).

It can be divided in two parts, 664 and 445403, that multiplied together give a palindrome (295747592).

The spelling of 664445403 in words is "six hundred sixty-four million, four hundred forty-five thousand, four hundred three".