18936840 has 128 divisors (see below), whose sum is σ = 62496000. Its totient is φ = 4561920.

The previous prime is 18936829. The next prime is 18936893. The reversal of 18936840 is 4863981.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 95061 + ... + 95259.

It is an arithmetic number, because the mean of its divisors is an integer number (488250).

Almost surely, 2^18936840 is an apocalyptic number.

18936840 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 18936840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31248000).

18936840 is an abundant number, since it is smaller than the sum of its proper divisors (43559160).

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

18936840 is a wasteful number, since it uses less digits than its factorization.

18936840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287 (or 283 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 18936840 is about 4351.6479637029. The cubic root of 18936840 is about 266.5441590059.

The spelling of 18936840 in words is "eighteen million, nine hundred thirty-six thousand, eight hundred forty".