161228281 has 8 divisors (see below), whose sum is σ = 170856000. Its totient is φ = 151714800.

The previous prime is 161228273. The next prime is 161228293. The reversal of 161228281 is 182822161.

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 161228281 - 2³ = 161228273 is a prime.

It is a super-2 number, since 2×161228281² = 51989117188429922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161228201) 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, 25645 + ... + 31306.

It is an arithmetic number, because the mean of its divisors is an integer number (21357000).

Almost surely, 2^161228281 is an apocalyptic number.

It is an amenable number.

161228281 is a deficient number, since it is larger than the sum of its proper divisors (9627719).

161228281 is a wasteful number, since it uses less digits than its factorization.

161228281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57119.

The product of its digits is 3072, while the sum is 31.

The square root of 161228281 is about 12697.5698856120. The cubic root of 161228281 is about 544.2691783929.

The spelling of 161228281 in words is "one hundred sixty-one million, two hundred twenty-eight thousand, two hundred eighty-one".