28670989 has 2 divisors, whose sum is σ = 28670990. Its totient is φ = 28670988.

The previous prime is 28670953. The next prime is 28671011. The reversal of 28670989 is 98907682.

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., 17892900 + 10778089 = 4230^2 + 3283^2 .

It is a cyclic number.

It is not a de Polignac number, because 28670989 - 2⁷ = 28670861 is a prime.

It is a super-2 number, since 2×28670989² = 1644051220476242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28670909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14335494 + 14335495.

It is an arithmetic number, because the mean of its divisors is an integer number (14335495).

Almost surely, 2^28670989 is an apocalyptic number.

It is an amenable number.

28670989 is a deficient number, since it is larger than the sum of its proper divisors (1).

28670989 is an equidigital number, since it uses as much as digits as its factorization.

28670989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 435456, while the sum is 49.

The square root of 28670989 is about 5354.5297646012. The cubic root of 28670989 is about 306.0653917805.

The spelling of 28670989 in words is "twenty-eight million, six hundred seventy thousand, nine hundred eighty-nine".