18936540 has 216 divisors, whose sum is σ = 70958160. Its totient is φ = 4064256.

The previous prime is 18936523. The next prime is 18936557. The reversal of 18936540 is 4563981.

18936540 is a `hidden beast` number, since 1 + 89 + 36 + 540 = 666.

It is an interprime number because it is at equal distance from previous prime (18936523) and next prime (18936557).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18936495 and 18936504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 167524 + ... + 167636.

It is an arithmetic number, because the mean of its divisors is an integer number (328510).

Almost surely, 2^18936540 is an apocalyptic number.

18936540 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 18936540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35479080).

18936540 is an abundant number, since it is smaller than the sum of its proper divisors (52021620).

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

18936540 is a wasteful number, since it uses less digits than its factorization.

18936540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 18936540 is about 4351.6134938664. The cubic root of 18936540 is about 266.5427514555.

The spelling of 18936540 in words is "eighteen million, nine hundred thirty-six thousand, five hundred forty".