28576621 has 2 divisors, whose sum is σ = 28576622. Its totient is φ = 28576620.

The previous prime is 28576619. The next prime is 28576663. The reversal of 28576621 is 12667582.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19053225 + 9523396 = 4365^2 + 3086^2 .

It is a cyclic number.

It is not a de Polignac number, because 28576621 - 2¹ = 28576619 is a prime.

Together with 28576619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28576021) 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 as a sum of consecutive naturals, namely, 14288310 + 14288311.

It is an arithmetic number, because the mean of its divisors is an integer number (14288311).

Almost surely, 2^28576621 is an apocalyptic number.

It is an amenable number.

28576621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28576621 is an equidigital number, since it uses as much as digits as its factorization.

28576621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 37.

The square root of 28576621 is about 5345.7105234010. The cubic root of 28576621 is about 305.7292270563.

The spelling of 28576621 in words is "twenty-eight million, five hundred seventy-six thousand, six hundred twenty-one".