18941636 has 36 divisors (see below), whose sum is σ = 38816316. Its totient is φ = 8064000.

The previous prime is 18941633. The next prime is 18941707. The reversal of 18941636 is 63614981.

It can be written as a sum of positive squares in 2 ways, for example, as 17172736 + 1768900 = 4144^2 + 1330^2 .

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 18941636.

It is not an unprimeable number, because it can be changed into a prime (18941633) 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, 47036 + ... + 47436.

It is an arithmetic number, because the mean of its divisors is an integer number (1078231).

Almost surely, 2^18941636 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 18941636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19408158).

18941636 is an abundant number, since it is smaller than the sum of its proper divisors (19874680).

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

18941636 is a wasteful number, since it uses less digits than its factorization.

18941636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660 (or 651 counting only the distinct ones).

The product of its digits is 31104, while the sum is 38.

The square root of 18941636 is about 4352.1989844216. The cubic root of 18941636 is about 266.5666590267.

The spelling of 18941636 in words is "eighteen million, nine hundred forty-one thousand, six hundred thirty-six".