664778363 has 2 divisors, whose sum is σ = 664778364. Its totient is φ = 664778362.

The previous prime is 664778351. The next prime is 664778423. The reversal of 664778363 is 363877466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664778363 - 2⁴ = 664778347 is a prime.

It is not a weakly prime, because it can be changed into another prime (664778333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332389181 + 332389182.

It is an arithmetic number, because the mean of its divisors is an integer number (332389182).

Almost surely, 2^664778363 is an apocalyptic number.

664778363 is a deficient number, since it is larger than the sum of its proper divisors (1).

664778363 is an equidigital number, since it uses as much as digits as its factorization.

664778363 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3048192, while the sum is 50.

The square root of 664778363 is about 25783.2962012230. The cubic root of 664778363 is about 872.7548921818.

The spelling of 664778363 in words is "six hundred sixty-four million, seven hundred seventy-eight thousand, three hundred sixty-three".