309973716 has 252 divisors, whose sum is σ = 957690972. Its totient is φ = 87340032.

The previous prime is 309973693. The next prime is 309973723. The reversal of 309973716 is 617379903.

It can be written as a sum of positive squares in 6 ways, for example, as 72900 + 309900816 = 270^2 + 17604^2 .

It is a super-2 number, since 2×309973716² = 192167409221697312, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 8377650 + ... + 8377686.

It is an arithmetic number, because the mean of its divisors is an integer number (3800361).

Almost surely, 2^309973716 is an apocalyptic number.

309973716 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 309973716, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (478845486).

309973716 is an abundant number, since it is smaller than the sum of its proper divisors (647717256).

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

309973716 is a wasteful number, since it uses less digits than its factorization.

309973716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 214326, while the sum is 45.

The square root of 309973716 is about 17606.0704303942. The cubic root of 309973716 is about 676.7708169852.

The spelling of 309973716 in words is "three hundred nine million, nine hundred seventy-three thousand, seven hundred sixteen".