28158649 has 2 divisors, whose sum is σ = 28158650. Its totient is φ = 28158648.

The previous prime is 28158617. The next prime is 28158659. The reversal of 28158649 is 94685182.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27405225 + 753424 = 5235^2 + 868^2 .

It is a cyclic number.

It is not a de Polignac number, because 28158649 - 2⁵ = 28158617 is a prime.

It is not a weakly prime, because it can be changed into another prime (28158659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14079324 + 14079325.

It is an arithmetic number, because the mean of its divisors is an integer number (14079325).

Almost surely, 2^28158649 is an apocalyptic number.

It is an amenable number.

28158649 is a deficient number, since it is larger than the sum of its proper divisors (1).

28158649 is an equidigital number, since it uses as much as digits as its factorization.

28158649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 138240, while the sum is 43.

The square root of 28158649 is about 5306.4723687211. The cubic root of 28158649 is about 304.2313314528.

The spelling of 28158649 in words is "twenty-eight million, one hundred fifty-eight thousand, six hundred forty-nine".