865537989 has 16 divisors (see below), whose sum is σ = 1217630400. Its totient is φ = 545377536.

The previous prime is 865537969. The next prime is 865537999. The reversal of 865537989 is 989735568.

It is a de Polignac number, because none of the positive numbers 2^k-865537989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (865537919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7147 + ... + 42215.

It is an arithmetic number, because the mean of its divisors is an integer number (76101900).

Almost surely, 2^865537989 is an apocalyptic number.

It is an amenable number.

865537989 is a deficient number, since it is larger than the sum of its proper divisors (352092411).

865537989 is a wasteful number, since it uses less digits than its factorization.

865537989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35524.

The product of its digits is 16329600, while the sum is 60.

The square root of 865537989 is about 29420.0270054261. The cubic root of 865537989 is about 953.0054363094.

The spelling of 865537989 in words is "eight hundred sixty-five million, five hundred thirty-seven thousand, nine hundred eighty-nine".