28291489 has 2 divisors, whose sum is σ = 28291490. Its totient is φ = 28291488.

The previous prime is 28291481. The next prime is 28291507. The reversal of 28291489 is 98419282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28005264 + 286225 = 5292^2 + 535^2 .

It is a cyclic number.

It is not a de Polignac number, because 28291489 - 2³ = 28291481 is a prime.

It is not a weakly prime, because it can be changed into another prime (28291481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14145744 + 14145745.

It is an arithmetic number, because the mean of its divisors is an integer number (14145745).

Almost surely, 2^28291489 is an apocalyptic number.

It is an amenable number.

28291489 is a deficient number, since it is larger than the sum of its proper divisors (1).

28291489 is an equidigital number, since it uses as much as digits as its factorization.

28291489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 43.

The square root of 28291489 is about 5318.9744312226. The cubic root of 28291489 is about 304.7089905455.

The spelling of 28291489 in words is "twenty-eight million, two hundred ninety-one thousand, four hundred eighty-nine".