664487784437 has 2 divisors, whose sum is σ = 664487784438. Its totient is φ = 664487784436.

The previous prime is 664487784421. The next prime is 664487784503. The reversal of 664487784437 is 734487784466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 506931184081 + 157556600356 = 711991^2 + 396934^2 .

It is a cyclic number.

It is not a de Polignac number, because 664487784437 - 2⁴ = 664487784421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664487781437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332243892218 + 332243892219.

It is an arithmetic number, because the mean of its divisors is an integer number (332243892219).

Almost surely, 2^664487784437 is an apocalyptic number.

It is an amenable number.

664487784437 is a deficient number, since it is larger than the sum of its proper divisors (1).

664487784437 is an equidigital number, since it uses as much as digits as its factorization.

664487784437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 606928896, while the sum is 68.

The spelling of 664487784437 in words is "six hundred sixty-four billion, four hundred eighty-seven million, seven hundred eighty-four thousand, four hundred thirty-seven".