857745653617 has 4 divisors (see below), whose sum is σ = 857748090276. Its totient is φ = 857743216960.

The previous prime is 857745653573. The next prime is 857745653683. The reversal of 857745653617 is 716356547758.

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 650029387536 + 207716266081 = 806244^2 + 455759^2 .

It is a cyclic number.

It is not a de Polignac number, because 857745653617 - 2⁷ = 857745653489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (857745651617) 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, 578188 + ... + 1431709.

It is an arithmetic number, because the mean of its divisors is an integer number (214437022569).

Almost surely, 2^857745653617 is an apocalyptic number.

It is an amenable number.

857745653617 is a deficient number, since it is larger than the sum of its proper divisors (2436659).

857745653617 is a wasteful number, since it uses less digits than its factorization.

857745653617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2436658.

The product of its digits is 148176000, while the sum is 64.

The spelling of 857745653617 in words is "eight hundred fifty-seven billion, seven hundred forty-five million, six hundred fifty-three thousand, six hundred seventeen".