28959521989 has 2 divisors, whose sum is σ = 28959521990. Its totient is φ = 28959521988.

The previous prime is 28959521959. The next prime is 28959522017. The reversal of 28959521989 is 98912595982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22039777764 + 6919744225 = 148458^2 + 83185^2 .

It is a cyclic number.

It is not a de Polignac number, because 28959521989 - 2²³ = 28951133381 is a prime.

It is a super-2 number, since 2×28959521989² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28959521939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14479760994 + 14479760995.

It is an arithmetic number, because the mean of its divisors is an integer number (14479760995).

Almost surely, 2^28959521989 is an apocalyptic number.

It is an amenable number.

28959521989 is a deficient number, since it is larger than the sum of its proper divisors (1).

28959521989 is an equidigital number, since it uses as much as digits as its factorization.

28959521989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41990400, while the sum is 67.

The spelling of 28959521989 in words is "twenty-eight billion, nine hundred fifty-nine million, five hundred twenty-one thousand, nine hundred eighty-nine".