857144928581 has 4 divisors (see below), whose sum is σ = 857260594464. Its totient is φ = 857029262700.

The previous prime is 857144928571. The next prime is 857144928583. The reversal of 857144928581 is 185829441758.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857144928581 is a prime.

It is a super-2 number, since 2×857144928581² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857144928583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57821825 + ... + 57836646.

It is an arithmetic number, because the mean of its divisors is an integer number (214315148616).

Almost surely, 2^857144928581 is an apocalyptic number.

It is an amenable number.

857144928581 is a deficient number, since it is larger than the sum of its proper divisors (115665883).

857144928581 is a wasteful number, since it uses less digits than its factorization.

857144928581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115665882.

The product of its digits is 25804800, while the sum is 62.

The spelling of 857144928581 in words is "eight hundred fifty-seven billion, one hundred forty-four million, nine hundred twenty-eight thousand, five hundred eighty-one".