665505803 has 2 divisors, whose sum is σ = 665505804. Its totient is φ = 665505802.

The previous prime is 665505767. The next prime is 665505823. The reversal of 665505803 is 308505566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665505803 - 2¹⁰ = 665504779 is a prime.

It is not a weakly prime, because it can be changed into another prime (665505823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332752901 + 332752902.

It is an arithmetic number, because the mean of its divisors is an integer number (332752902).

Almost surely, 2^665505803 is an apocalyptic number.

665505803 is a deficient number, since it is larger than the sum of its proper divisors (1).

665505803 is an equidigital number, since it uses as much as digits as its factorization.

665505803 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 665505803 is about 25797.3991518525. The cubic root of 665505803 is about 873.0731162303.

The spelling of 665505803 in words is "six hundred sixty-five million, five hundred five thousand, eight hundred three".