660213745 has 4 divisors (see below), whose sum is σ = 792256500. Its totient is φ = 528170992.

The previous prime is 660213709. The next prime is 660213761. The reversal of 660213745 is 547312066.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 117137329 + 543076416 = 10823^2 + 23304^2 .

It is a cyclic number.

It is not a de Polignac number, because 660213745 - 2¹⁷ = 660082673 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 660213745.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66021370 + ... + 66021379.

It is an arithmetic number, because the mean of its divisors is an integer number (198064125).

Almost surely, 2^660213745 is an apocalyptic number.

It is an amenable number.

660213745 is a deficient number, since it is larger than the sum of its proper divisors (132042755).

660213745 is a wasteful number, since it uses less digits than its factorization.

660213745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132042754.

The product of its (nonzero) digits is 30240, while the sum is 34.

The square root of 660213745 is about 25694.6248269945. The cubic root of 660213745 is about 870.7527483459.

The spelling of 660213745 in words is "six hundred sixty million, two hundred thirteen thousand, seven hundred forty-five".