28788521 has 2 divisors, whose sum is σ = 28788522. Its totient is φ = 28788520.

The previous prime is 28788517. The next prime is 28788541. The reversal of 28788521 is 12588782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16810000 + 11978521 = 4100^2 + 3461^2 .

It is a cyclic number.

It is not a de Polignac number, because 28788521 - 2² = 28788517 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28788541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14394260 + 14394261.

It is an arithmetic number, because the mean of its divisors is an integer number (14394261).

Almost surely, 2^28788521 is an apocalyptic number.

It is an amenable number.

28788521 is a deficient number, since it is larger than the sum of its proper divisors (1).

28788521 is an equidigital number, since it uses as much as digits as its factorization.

28788521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 71680, while the sum is 41.

The square root of 28788521 is about 5365.4935467299. The cubic root of 28788521 is about 306.4830431661.

The spelling of 28788521 in words is "twenty-eight million, seven hundred eighty-eight thousand, five hundred twenty-one".