664884397 has 2 divisors, whose sum is σ = 664884398. Its totient is φ = 664884396.

The previous prime is 664884383. The next prime is 664884401. The reversal of 664884397 is 793488466.

664884397 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 503822916 + 161061481 = 22446^2 + 12691^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664884397 is a prime.

It is a super-2 number, since 2×664884397² = 884142522748107218, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664884317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332442198 + 332442199.

It is an arithmetic number, because the mean of its divisors is an integer number (332442199).

Almost surely, 2^664884397 is an apocalyptic number.

It is an amenable number.

664884397 is a deficient number, since it is larger than the sum of its proper divisors (1).

664884397 is an equidigital number, since it uses as much as digits as its factorization.

664884397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6967296, while the sum is 55.

The square root of 664884397 is about 25785.3523730043. The cubic root of 664884397 is about 872.8012919934.

It can be divided in two parts, 664884 and 397, that added together give a triangular number (665281 = T₁₁₅₃).

The spelling of 664884397 in words is "six hundred sixty-four million, eight hundred eighty-four thousand, three hundred ninety-seven".