857221605 has 24 divisors (see below), whose sum is σ = 1486753632. Its totient is φ = 456907104.

The previous prime is 857221577. The next prime is 857221627. The reversal of 857221605 is 506122758.

It is a happy number.

857221605 is a `hidden beast` number, since 8 + 572 + 21 + 60 + 5 = 666.

It is not a de Polignac number, because 857221605 - 2⁹ = 857221093 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 857221605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 84622 + ... + 94208.

It is an arithmetic number, because the mean of its divisors is an integer number (61948068).

Almost surely, 2^857221605 is an apocalyptic number.

It is an amenable number.

857221605 is a deficient number, since it is larger than the sum of its proper divisors (629532027).

857221605 is a wasteful number, since it uses less digits than its factorization.

857221605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11585 (or 11582 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 857221605 is about 29278.3470332599. The cubic root of 857221605 is about 949.9433410345.

The spelling of 857221605 in words is "eight hundred fifty-seven million, two hundred twenty-one thousand, six hundred five".