309989712 has 80 divisors (see below), whose sum is σ = 848913920. Its totient is φ = 97200000.

The previous prime is 309989711. The next prime is 309989741. The reversal of 309989712 is 217989903.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309989711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136587 + ... + 138837.

It is an arithmetic number, because the mean of its divisors is an integer number (10611424).

Almost surely, 2^309989712 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 309989712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (424456960).

309989712 is an abundant number, since it is smaller than the sum of its proper divisors (538924208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

309989712 is a wasteful number, since it uses less digits than its factorization.

309989712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2432 (or 2426 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 48.

The square root of 309989712 is about 17606.5246996675. The cubic root of 309989712 is about 676.7824582301.

The spelling of 309989712 in words is "three hundred nine million, nine hundred eighty-nine thousand, seven hundred twelve".