18413538 has 48 divisors (see below), whose sum is σ = 43615488. Its totient is φ = 5148000.

The previous prime is 18413537. The next prime is 18413561. The reversal of 18413538 is 83531481.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 18413499 and 18413508.

It is not an unprimeable number, because it can be changed into a prime (18413537) 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, 8463 + ... + 10413.

It is an arithmetic number, because the mean of its divisors is an integer number (908656).

Almost surely, 2^18413538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18413538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21807744).

18413538 is an abundant number, since it is smaller than the sum of its proper divisors (25201950).

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

18413538 is a wasteful number, since it uses less digits than its factorization.

18413538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1991 (or 1980 counting only the distinct ones).

The product of its digits is 11520, while the sum is 33.

The square root of 18413538 is about 4291.0998590105. The cubic root of 18413538 is about 264.0659557430.

The spelling of 18413538 in words is "eighteen million, four hundred thirteen thousand, five hundred thirty-eight".