18859860 has 72 divisors (see below), whose sum is σ = 59197320. Its totient is φ = 4854528.

The previous prime is 18859853. The next prime is 18859861. The reversal of 18859860 is 6895881.

It can be written as a sum of positive squares in 4 ways, for example, as 41616 + 18818244 = 204^2 + 4338^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18859861) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3414 + ... + 7026.

It is an arithmetic number, because the mean of its divisors is an integer number (822185).

Almost surely, 2^18859860 is an apocalyptic number.

18859860 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 18859860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29598660).

18859860 is an abundant number, since it is smaller than the sum of its proper divisors (40337460).

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

18859860 is a wasteful number, since it uses less digits than its factorization.

18859860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3657 (or 3652 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 45.

The square root of 18859860 is about 4342.7940314963. The cubic root of 18859860 is about 266.1824929692.

The spelling of 18859860 in words is "eighteen million, eight hundred fifty-nine thousand, eight hundred sixty".