18874638 has 48 divisors (see below), whose sum is σ = 43414800. Its totient is φ = 5909760.

The previous prime is 18874633. The next prime is 18874643. The reversal of 18874638 is 83647881.

18874638 is a `hidden beast` number, since 1 + 8 + 8 + 7 + 4 + 638 = 666.

It is an interprime number because it is at equal distance from previous prime (18874633) and next prime (18874643).

It is a junction number, because it is equal to n+sod(n) for n = 18874593 and 18874602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18874633) 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, 78198 + ... + 78438.

It is an arithmetic number, because the mean of its divisors is an integer number (904475).

Almost surely, 2^18874638 is an apocalyptic number.

18874638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18874638 is the 2748-th heptagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18874638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21707400).

18874638 is an abundant number, since it is smaller than the sum of its proper divisors (24540162).

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

18874638 is a wasteful number, since it uses less digits than its factorization.

18874638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 497 (or 494 counting only the distinct ones).

The product of its digits is 258048, while the sum is 45.

The square root of 18874638 is about 4344.4951375275. The cubic root of 18874638 is about 266.2519989270.

The spelling of 18874638 in words is "eighteen million, eight hundred seventy-four thousand, six hundred thirty-eight".