861900 has 108 divisors (see below), whose sum is σ = 2859192. Its totient is φ = 199680.

The previous prime is 861899. The next prime is 861901. The reversal of 861900 is 9168.

861900 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (861899) and next prime (861901).

It is a super-2 number, since 2×861900² = 1485743220000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (861901) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 50692 + ... + 50708.

It is an arithmetic number, because the mean of its divisors is an integer number (26474).

2⁸⁶¹⁹⁰⁰ 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 861900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1429596).

861900 is an abundant number, since it is smaller than the sum of its proper divisors (1997292).

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

861900 is a wasteful number, since it uses less digits than its factorization.

861900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 861900 is about 928.3856957106. The cubic root of 861900 is about 95.1668351864.

The spelling of 861900 in words is "eight hundred sixty-one thousand, nine hundred".