161221303 has 8 divisors (see below), whose sum is σ = 163870928. Its totient is φ = 158583744.

The previous prime is 161221261. The next prime is 161221309. The reversal of 161221303 is 303122161.

161221303 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 161221303 - 2⁹ = 161220791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161221309) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26200 + ... + 31762.

It is an arithmetic number, because the mean of its divisors is an integer number (20483866).

Almost surely, 2^161221303 is an apocalyptic number.

161221303 is a deficient number, since it is larger than the sum of its proper divisors (2649625).

161221303 is an equidigital number, since it uses as much as digits as its factorization.

161221303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6033.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 161221303 is about 12697.2951056514. The cubic root of 161221303 is about 544.2613262446.

Adding to 161221303 its reverse (303122161), we get a palindrome (464343464).

The spelling of 161221303 in words is "one hundred sixty-one million, two hundred twenty-one thousand, three hundred three".