661296329 has 4 divisors (see below), whose sum is σ = 661633476. Its totient is φ = 660959184.

The previous prime is 661296323. The next prime is 661296331. The reversal of 661296329 is 923692166.

661296329 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.

It can be written as a sum of positive squares in 2 ways, for example, as 449652025 + 211644304 = 21205^2 + 14548^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661296329 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 661296329.

It is not an unprimeable number, because it can be changed into a prime (661296323) 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, 165614 + ... + 169559.

It is an arithmetic number, because the mean of its divisors is an integer number (165408369).

Almost surely, 2^661296329 is an apocalyptic number.

It is an amenable number.

661296329 is a deficient number, since it is larger than the sum of its proper divisors (337147).

661296329 is a wasteful number, since it uses less digits than its factorization.

661296329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337146.

The product of its digits is 209952, while the sum is 44.

The square root of 661296329 is about 25715.6825497594. The cubic root of 661296329 is about 871.2284267284.

The spelling of 661296329 in words is "six hundred sixty-one million, two hundred ninety-six thousand, three hundred twenty-nine".