661330003 has 4 divisors (see below), whose sum is σ = 662190760. Its totient is φ = 660469248.

The previous prime is 661329989. The next prime is 661330009. The reversal of 661330003 is 300033166.

It is a happy number.

661330003 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 300033166 = 2 ⋅150016583.

It is a cyclic number.

It is not a de Polignac number, because 661330003 - 2²⁵ = 627775571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661330009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 429225 + ... + 430762.

It is an arithmetic number, because the mean of its divisors is an integer number (165547690).

Almost surely, 2^661330003 is an apocalyptic number.

661330003 is a deficient number, since it is larger than the sum of its proper divisors (860757).

661330003 is an equidigital number, since it uses as much as digits as its factorization.

661330003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860756.

The product of its (nonzero) digits is 972, while the sum is 22.

The square root of 661330003 is about 25716.3372780806. The cubic root of 661330003 is about 871.2432144752.

Adding to 661330003 its reverse (300033166), we get a palindrome (961363169).

The spelling of 661330003 in words is "six hundred sixty-one million, three hundred thirty thousand, three".