665650877 has 2 divisors, whose sum is σ = 665650878. Its totient is φ = 665650876.

The previous prime is 665650837. The next prime is 665650927. The reversal of 665650877 is 778056566.

It is a happy number.

It is an a-pointer prime, because the next prime (665650927) can be obtained adding 665650877 to its sum of digits (50).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 425431876 + 240219001 = 20626^2 + 15499^2 .

It is a cyclic number.

It is not a de Polignac number, because 665650877 - 2⁶ = 665650813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665650837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332825438 + 332825439.

It is an arithmetic number, because the mean of its divisors is an integer number (332825439).

Almost surely, 2^665650877 is an apocalyptic number.

It is an amenable number.

665650877 is a deficient number, since it is larger than the sum of its proper divisors (1).

665650877 is an equidigital number, since it uses as much as digits as its factorization.

665650877 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2116800, while the sum is 50.

The square root of 665650877 is about 25800.2107937125. The cubic root of 665650877 is about 873.1365521945.

The spelling of 665650877 in words is "six hundred sixty-five million, six hundred fifty thousand, eight hundred seventy-seven".