660506537 has 4 divisors (see below), whose sum is σ = 666566340. Its totient is φ = 654446736.

The previous prime is 660506513. The next prime is 660506549. The reversal of 660506537 is 735605066.

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 155650576 + 504855961 = 12476^2 + 22469^2 .

It is a cyclic number.

It is not a de Polignac number, because 660506537 - 2¹² = 660502441 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 660506537.

It is not an unprimeable number, because it can be changed into a prime (660509537) by changing a digit.

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, 3029738 + ... + 3029955.

It is an arithmetic number, because the mean of its divisors is an integer number (166641585).

Almost surely, 2^660506537 is an apocalyptic number.

It is an amenable number.

660506537 is a deficient number, since it is larger than the sum of its proper divisors (6059803).

660506537 is a wasteful number, since it uses less digits than its factorization.

660506537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6059802.

The product of its (nonzero) digits is 113400, while the sum is 38.

The square root of 660506537 is about 25700.3217295037. The cubic root of 660506537 is about 870.8814499780.

The spelling of 660506537 in words is "six hundred sixty million, five hundred six thousand, five hundred thirty-seven".