664969369 has 9 divisors (see below), whose sum is σ = 674038911. Its totient is φ = 656021280.

The previous prime is 664969343. The next prime is 664969379. The reversal of 664969369 is 963969466.

The square root of 664969369 is 25787.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 500103769 + 164865600 = 22363^2 + 12840^2 .

It is not a de Polignac number, because 664969369 - 2¹³ = 664961177 is a prime.

It is a super-2 number, since 2×664969369² = 884368523416516322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664969379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2759089 + ... + 2759329.

Almost surely, 2^664969369 is an apocalyptic number.

664969369 is the 25787-th square number.

664969369 is the 12894-th centered octagonal number.

It is an amenable number.

664969369 is a deficient number, since it is larger than the sum of its proper divisors (9069542).

664969369 is an frugal number, since it uses more digits than its factorization.

664969369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696 (or 348 counting only the distinct ones).

The product of its digits is 11337408, while the sum is 58.

The cubic root of 664969369 is about 872.8384716458.

The spelling of 664969369 in words is "six hundred sixty-four million, nine hundred sixty-nine thousand, three hundred sixty-nine".