28691161 has 2 divisors, whose sum is σ = 28691162. Its totient is φ = 28691160.

The previous prime is 28691153. The next prime is 28691177. The reversal of 28691161 is 16119682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28515600 + 175561 = 5340^2 + 419^2 .

It is a cyclic number.

It is not a de Polignac number, because 28691161 - 2³ = 28691153 is a prime.

It is not a weakly prime, because it can be changed into another prime (28691261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14345580 + 14345581.

It is an arithmetic number, because the mean of its divisors is an integer number (14345581).

Almost surely, 2^28691161 is an apocalyptic number.

It is an amenable number.

28691161 is a deficient number, since it is larger than the sum of its proper divisors (1).

28691161 is an equidigital number, since it uses as much as digits as its factorization.

28691161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 28691161 is about 5356.4130721967. The cubic root of 28691161 is about 306.1371542592.

The spelling of 28691161 in words is "twenty-eight million, six hundred ninety-one thousand, one hundred sixty-one".