858782861 has 4 divisors (see below), whose sum is σ = 858929724. Its totient is φ = 858636000.

The previous prime is 858782831. The next prime is 858782879. The reversal of 858782861 is 168287858.

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 224700100 + 634082761 = 14990^2 + 25181^2 .

It is a cyclic number.

It is not a de Polignac number, because 858782861 - 2²² = 854588557 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 (858782831) 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, 64280 + ... + 76481.

It is an arithmetic number, because the mean of its divisors is an integer number (214732431).

Almost surely, 2^858782861 is an apocalyptic number.

It is an amenable number.

858782861 is a deficient number, since it is larger than the sum of its proper divisors (146863).

858782861 is a wasteful number, since it uses less digits than its factorization.

858782861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146862.

The product of its digits is 1720320, while the sum is 53.

The square root of 858782861 is about 29304.9972018426. The cubic root of 858782861 is about 950.5197012391.

The spelling of 858782861 in words is "eight hundred fifty-eight million, seven hundred eighty-two thousand, eight hundred sixty-one".