871857049 has 24 divisors (see below), whose sum is σ = 1044291528. Its totient is φ = 725437440.

The previous prime is 871857043. The next prime is 871857137. The reversal of 871857049 is 940758178.

It can be written as a sum of positive squares in 4 ways, for example, as 85895824 + 785961225 = 9268^2 + 28035^2 .

It is not a de Polignac number, because 871857049 - 2²⁵ = 838302617 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a junction number, because it is equal to n+sod(n) for n = 871856993 and 871857011.

It is not an unprimeable number, because it can be changed into a prime (871857043) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 250179 + ... + 253639.

It is an arithmetic number, because the mean of its divisors is an integer number (43512147).

Almost surely, 2^871857049 is an apocalyptic number.

It is an amenable number.

871857049 is a deficient number, since it is larger than the sum of its proper divisors (172434479).

871857049 is a wasteful number, since it uses less digits than its factorization.

871857049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3625 (or 3618 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 49.

The square root of 871857049 is about 29527.2255554090. The cubic root of 871857049 is about 955.3190272096.

The spelling of 871857049 in words is "eight hundred seventy-one million, eight hundred fifty-seven thousand, forty-nine".