28661203 has 4 divisors (see below), whose sum is σ = 28684440. Its totient is φ = 28637968.

The previous prime is 28661189. The next prime is 28661219. The reversal of 28661203 is 30216682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30216682 = 2 ⋅15108341.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28661203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28661803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9658 + ... + 12271.

It is an arithmetic number, because the mean of its divisors is an integer number (7171110).

Almost surely, 2^28661203 is an apocalyptic number.

28661203 is a deficient number, since it is larger than the sum of its proper divisors (23237).

28661203 is a wasteful number, since it uses less digits than its factorization.

28661203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23236.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 28661203 is about 5353.6158808790. The cubic root of 28661203 is about 306.0305656739.

Adding to 28661203 its reverse (30216682), we get a palindrome (58877885).

The spelling of 28661203 in words is "twenty-eight million, six hundred sixty-one thousand, two hundred three".