309696660 has 432 divisors, whose sum is σ = 1225210896. Its totient is φ = 62705664.

The previous prime is 309696659. The next prime is 309696683. The reversal of 309696660 is 66696903.

It can be written as a sum of positive squares in 8 ways, for example, as 7056 + 309689604 = 84^2 + 17598^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 4242384 + ... + 4242456.

Almost surely, 2^309696660 is an apocalyptic number.

309696660 is a gapful number since it is divisible by the number (30) 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 309696660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (612605448).

309696660 is an abundant number, since it is smaller than the sum of its proper divisors (915514236).

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

309696660 is a wasteful number, since it uses less digits than its factorization.

309696660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 140 counting only the distinct ones).

The product of its (nonzero) digits is 314928, while the sum is 45.

The square root of 309696660 is about 17598.2004761851. The cubic root of 309696660 is about 676.5691232099.

The spelling of 309696660 in words is "three hundred nine million, six hundred ninety-six thousand, six hundred sixty".