661361003 has 2 divisors, whose sum is σ = 661361004. Its totient is φ = 661361002.

The previous prime is 661360969. The next prime is 661361011. The reversal of 661361003 is 300163166.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 661361003 - 2⁶ = 661360939 is a prime.

It is not a weakly prime, because it can be changed into another prime (661361023) 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, 330680501 + 330680502.

It is an arithmetic number, because the mean of its divisors is an integer number (330680502).

Almost surely, 2^661361003 is an apocalyptic number.

661361003 is a deficient number, since it is larger than the sum of its proper divisors (1).

661361003 is an equidigital number, since it uses as much as digits as its factorization.

661361003 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 661361003 is about 25716.9400007077. The cubic root of 661361003 is about 871.2568275063.

The spelling of 661361003 in words is "six hundred sixty-one million, three hundred sixty-one thousand, three".