866257613 has 4 divisors (see below), whose sum is σ = 932892828. Its totient is φ = 799622400.

The previous prime is 866257607. The next prime is 866257631. The reversal of 866257613 is 316752668.

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 531440809 + 334816804 = 23053^2 + 18298^2 .

It is a cyclic number.

It is not a de Polignac number, because 866257613 - 2⁴ = 866257597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866257603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33317588 + ... + 33317613.

It is an arithmetic number, because the mean of its divisors is an integer number (233223207).

Almost surely, 2^866257613 is an apocalyptic number.

It is an amenable number.

866257613 is a deficient number, since it is larger than the sum of its proper divisors (66635215).

866257613 is a wasteful number, since it uses less digits than its factorization.

866257613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66635214.

The product of its digits is 362880, while the sum is 44.

The square root of 866257613 is about 29432.2546367077. The cubic root of 866257613 is about 953.2694784878.

The spelling of 866257613 in words is "eight hundred sixty-six million, two hundred fifty-seven thousand, six hundred thirteen".