1861860 has 192 divisors, whose sum is σ = 7225344. Its totient is φ = 345600.

The previous prime is 1861859. The next prime is 1861861. The reversal of 1861860 is 681681.

It is an interprime number because it is at equal distance from previous prime (1861859) and next prime (1861861).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1861861) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 60045 + ... + 60075.

It is an arithmetic number, because the mean of its divisors is an integer number (37632).

2^1861860 is an apocalyptic number.

1861860 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a pronic number, being equal to 1364×1365.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1861860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3612672).

1861860 is an abundant number, since it is smaller than the sum of its proper divisors (5363484).

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

1861860 is a wasteful number, since it uses less digits than its factorization.

1861860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 1861860 is about 1364.4999083913. The cubic root of 1861860 is about 123.0218746210.

Subtracting from 1861860 its product of nonzero digits (2304), we obtain a triangular number (1859556 = T₁₉₂₈).

The spelling of 1861860 in words is "one million, eight hundred sixty-one thousand, eight hundred sixty".