28513691 has 2 divisors, whose sum is σ = 28513692. Its totient is φ = 28513690.

The previous prime is 28513679. The next prime is 28513711. The reversal of 28513691 is 19631582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28513691 - 2¹⁰ = 28512667 is a prime.

It is not a weakly prime, because it can be changed into another prime (28513621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14256845 + 14256846.

It is an arithmetic number, because the mean of its divisors is an integer number (14256846).

Almost surely, 2^28513691 is an apocalyptic number.

28513691 is a deficient number, since it is larger than the sum of its proper divisors (1).

28513691 is an equidigital number, since it uses as much as digits as its factorization.

28513691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 35.

The square root of 28513691 is about 5339.8212516900. The cubic root of 28513691 is about 305.5046416007.

The spelling of 28513691 in words is "twenty-eight million, five hundred thirteen thousand, six hundred ninety-one".