856899810 has 160 divisors (see below), whose sum is σ = 2612554560. Its totient is φ = 199780992.

The previous prime is 856899809. The next prime is 856899811. The reversal of 856899810 is 18998658.

It is an interprime number because it is at equal distance from previous prime (856899809) and next prime (856899811).

It is a super-2 number, since 2×856899810² = 1468554568756072200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (856899811) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 197929 + ... + 202211.

It is an arithmetic number, because the mean of its divisors is an integer number (16328466).

Almost surely, 2^856899810 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 856899810, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1306277280).

856899810 is an abundant number, since it is smaller than the sum of its proper divisors (1755654750).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

856899810 is a wasteful number, since it uses less digits than its factorization.

856899810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4334 (or 4325 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 54.

The square root of 856899810 is about 29272.8510739900. The cubic root of 856899810 is about 949.8244587935.

The spelling of 856899810 in words is "eight hundred fifty-six million, eight hundred ninety-nine thousand, eight hundred ten".