28660901 has 4 divisors (see below), whose sum is σ = 28680204. Its totient is φ = 28641600.

The previous prime is 28660889. The next prime is 28660909. The reversal of 28660901 is 10906682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10906682 = 2 ⋅5453341.

It can be written as a sum of positive squares in 2 ways, for example, as 15007876 + 13653025 = 3874^2 + 3695^2 .

It is a cyclic number.

It is not a de Polignac number, because 28660901 - 2⁶ = 28660837 is a prime.

It is a super-2 number, since 2×28660901² = 1642894492263602, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28660909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7220 + ... + 10461.

It is an arithmetic number, because the mean of its divisors is an integer number (7170051).

Almost surely, 2^28660901 is an apocalyptic number.

It is an amenable number.

28660901 is a deficient number, since it is larger than the sum of its proper divisors (19303).

28660901 is a wasteful number, since it uses less digits than its factorization.

28660901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19302.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 28660901 is about 5353.5876755686. The cubic root of 28660901 is about 306.0294907998.

The spelling of 28660901 in words is "twenty-eight million, six hundred sixty thousand, nine hundred one".