320390661 has 8 divisors (see below), whose sum is σ = 427309920. Its totient is φ = 213532592.

The previous prime is 320390657. The next prime is 320390663. The reversal of 320390661 is 166093023.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 320390661 - 2² = 320390657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320390663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1230 + ... + 25343.

It is an arithmetic number, because the mean of its divisors is an integer number (53413740).

Almost surely, 2^320390661 is an apocalyptic number.

It is an amenable number.

320390661 is a deficient number, since it is larger than the sum of its proper divisors (106919259).

320390661 is a wasteful number, since it uses less digits than its factorization.

320390661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30595.

The product of its (nonzero) digits is 5832, while the sum is 30.

The square root of 320390661 is about 17899.4597963179. The cubic root of 320390661 is about 684.2686075265.

The spelling of 320390661 in words is "three hundred twenty million, three hundred ninety thousand, six hundred sixty-one".