28016399161 has 3 divisors (see below), whose sum is σ = 28016566543. Its totient is φ = 28016231780.

The previous prime is 28016399119. The next prime is 28016399197. The reversal of 28016399161 is 16199361082.

The square root of 28016399161 is 167381.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 27949486761 + 66912400 = 167181^2 + 8180^2 .

It is not a de Polignac number, because 28016399161 - 2²¹ = 28014302009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28016399101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 83691 + ... + 251071.

Almost surely, 2^28016399161 is an apocalyptic number.

28016399161 is the 167381-st square number.

28016399161 is the 83691-st centered octagonal number.

It is an amenable number.

28016399161 is a deficient number, since it is larger than the sum of its proper divisors (167382).

28016399161 is an frugal number, since it uses more digits than its factorization.

28016399161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334762 (or 167381 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 46.

The spelling of 28016399161 in words is "twenty-eight billion, sixteen million, three hundred ninety-nine thousand, one hundred sixty-one".