6661215305 has 8 divisors (see below), whose sum is σ = 7994215944. Its totient is φ = 5328467200.

The previous prime is 6661215283. The next prime is 6661215329. The reversal of 6661215305 is 5035121666.

It can be written as a sum of positive squares in 4 ways, for example, as 321233929 + 6339981376 = 17923^2 + 79624^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6661215305 - 2¹² = 6661211209 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 785 + ... + 115425.

It is an arithmetic number, because the mean of its divisors is an integer number (999276993).

Almost surely, 2^6661215305 is an apocalyptic number.

It is an amenable number.

6661215305 is a deficient number, since it is larger than the sum of its proper divisors (1333000639).

6661215305 is a wasteful number, since it uses less digits than its factorization.

6661215305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126267.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 6661215305 is about 81616.2686294834. The cubic root of 6661215305 is about 1881.5589250996.

The spelling of 6661215305 in words is "six billion, six hundred sixty-one million, two hundred fifteen thousand, three hundred five".