28039961 has 2 divisors, whose sum is σ = 28039962. Its totient is φ = 28039960.

The previous prime is 28039951. The next prime is 28039981. The reversal of 28039961 is 16993082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17799961 + 10240000 = 4219^2 + 3200^2 .

It is a cyclic number.

It is not a de Polignac number, because 28039961 - 2¹⁰ = 28038937 is a prime.

It is not a weakly prime, because it can be changed into another prime (28039951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14019980 + 14019981.

It is an arithmetic number, because the mean of its divisors is an integer number (14019981).

Almost surely, 2^28039961 is an apocalyptic number.

It is an amenable number.

28039961 is a deficient number, since it is larger than the sum of its proper divisors (1).

28039961 is an equidigital number, since it uses as much as digits as its factorization.

28039961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 28039961 is about 5295.2772354240. The cubic root of 28039961 is about 303.8032870097.

The spelling of 28039961 in words is "twenty-eight million, thirty-nine thousand, nine hundred sixty-one".