664843443425 has 12 divisors (see below), whose sum is σ = 942178137216. Its totient is φ = 455892646800.

The previous prime is 664843443419. The next prime is 664843443437. The reversal of 664843443425 is 524344348466.

It is a happy number.

It is not a de Polignac number, because 664843443425 - 2¹⁴ = 664843427041 is a prime.

It is a super-2 number, since 2×664843443425² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1899552521 + ... + 1899552870.

It is an arithmetic number, because the mean of its divisors is an integer number (78514844768).

Almost surely, 2^664843443425 is an apocalyptic number.

It is an amenable number.

664843443425 is a deficient number, since it is larger than the sum of its proper divisors (277334693791).

664843443425 is a wasteful number, since it uses less digits than its factorization.

664843443425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3799105408 (or 3799105403 counting only the distinct ones).

The product of its digits is 26542080, while the sum is 53.

The spelling of 664843443425 in words is "six hundred sixty-four billion, eight hundred forty-three million, four hundred forty-three thousand, four hundred twenty-five".