985491309 has 32 divisors (see below), whose sum is σ = 1520138880. Its totient is φ = 561254400.

The previous prime is 985491301. The next prime is 985491323. The reversal of 985491309 is 903194589.

It is not a de Polignac number, because 985491309 - 2³ = 985491301 is a prime.

It is a super-2 number, since 2×985491309² = 1942386240229066962, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (985491301) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 565179 + ... + 566919.

It is an arithmetic number, because the mean of its divisors is an integer number (47504340).

Almost surely, 2^985491309 is an apocalyptic number.

It is an amenable number.

985491309 is a deficient number, since it is larger than the sum of its proper divisors (534647571).

985491309 is a wasteful number, since it uses less digits than its factorization.

985491309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2781.

The product of its (nonzero) digits is 349920, while the sum is 48.

The square root of 985491309 is about 31392.5358803649. The cubic root of 985491309 is about 995.1401901744.

It can be divided in two parts, 985 and 491309, that added together give a palindrome (492294).

The spelling of 985491309 in words is "nine hundred eighty-five million, four hundred ninety-one thousand, three hundred nine".