28920530 has 8 divisors (see below), whose sum is σ = 52056972. Its totient is φ = 11568208.

The previous prime is 28920523. The next prime is 28920533. The reversal of 28920530 is 3502982.

It can be written as a sum of positive squares in 2 ways, for example, as 23222761 + 5697769 = 4819^2 + 2387^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28920493 and 28920502.

It is not an unprimeable number, because it can be changed into a prime (28920533) 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, 1446017 + ... + 1446036.

Almost surely, 2^28920530 is an apocalyptic number.

28920530 is a deficient number, since it is larger than the sum of its proper divisors (23136442).

28920530 is a wasteful number, since it uses less digits than its factorization.

28920530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2892060.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 28920530 is about 5377.7811409540. The cubic root of 28920530 is about 306.9507855765.

The spelling of 28920530 in words is "twenty-eight million, nine hundred twenty thousand, five hundred thirty".