1861100 has 36 divisors (see below), whose sum is σ = 4155984. Its totient is φ = 722880.

The previous prime is 1861081. The next prime is 1861103. The reversal of 1861100 is 11681.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1861103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3449 + ... + 3951.

It is an arithmetic number, because the mean of its divisors is an integer number (115444).

2^1861100 is an apocalyptic number.

1861100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1861100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2077992).

1861100 is an abundant number, since it is smaller than the sum of its proper divisors (2294884).

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

1861100 is a wasteful number, since it uses less digits than its factorization.

1861100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554 (or 547 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 17.

The square root of 1861100 is about 1364.2213896579. The cubic root of 1861100 is about 123.0051334143.

Adding to 1861100 its reverse (11681), we get a palindrome (1872781).

The spelling of 1861100 in words is "one million, eight hundred sixty-one thousand, one hundred".