861834100 has 72 divisors (see below), whose sum is σ = 1942875648. Its totient is φ = 331478400.

The previous prime is 861834041. The next prime is 861834109. The reversal of 861834100 is 1438168.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861834109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 535497 + ... + 537103.

It is an arithmetic number, because the mean of its divisors is an integer number (26984384).

Almost surely, 2^861834100 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861834100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (971437824).

861834100 is an abundant number, since it is smaller than the sum of its proper divisors (1081041548).

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

861834100 is a wasteful number, since it uses less digits than its factorization.

861834100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1825 (or 1818 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 861834100 is about 29357.0110876431. The cubic root of 861834100 is about 951.6440967136.

The spelling of 861834100 in words is "eight hundred sixty-one million, eight hundred thirty-four thousand, one hundred".