664851739 has 4 divisors (see below), whose sum is σ = 674215920. Its totient is φ = 655487560.

The previous prime is 664851683. The next prime is 664851809. The reversal of 664851739 is 937158466.

664851739 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 an emirpimes, since its reverse is a distinct semiprime: 937158466 = 2 ⋅468579233.

It is a cyclic number.

It is not a de Polignac number, because 664851739 - 2¹³ = 664843547 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 664851692 and 664851701.

It is not an unprimeable number, because it can be changed into a prime (664851839) 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, 4681984 + ... + 4682125.

It is an arithmetic number, because the mean of its divisors is an integer number (168553980).

Almost surely, 2^664851739 is an apocalyptic number.

664851739 is a deficient number, since it is larger than the sum of its proper divisors (9364181).

664851739 is an equidigital number, since it uses as much as digits as its factorization.

664851739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9364180.

The product of its digits is 1088640, while the sum is 49.

The square root of 664851739 is about 25784.7190987220. The cubic root of 664851739 is about 872.7870015837.

The spelling of 664851739 in words is "six hundred sixty-four million, eight hundred fifty-one thousand, seven hundred thirty-nine".