28989661 has 2 divisors, whose sum is σ = 28989662. Its totient is φ = 28989660.

The previous prime is 28989643. The next prime is 28989673. The reversal of 28989661 is 16698982.

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., 20025625 + 8964036 = 4475^2 + 2994^2 .

It is a cyclic number.

It is not a de Polignac number, because 28989661 - 2⁵ = 28989629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28989691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14494830 + 14494831.

It is an arithmetic number, because the mean of its divisors is an integer number (14494831).

Almost surely, 2^28989661 is an apocalyptic number.

It is an amenable number.

28989661 is a deficient number, since it is larger than the sum of its proper divisors (1).

28989661 is an equidigital number, since it uses as much as digits as its factorization.

28989661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 373248, while the sum is 49.

The square root of 28989661 is about 5384.2047695087. The cubic root of 28989661 is about 307.1951670981.

The spelling of 28989661 in words is "twenty-eight million, nine hundred eighty-nine thousand, six hundred sixty-one".