18471240 has 80 divisors (see below), whose sum is σ = 62094780. Its totient is φ = 4924800.

The previous prime is 18471199. The next prime is 18471241. The reversal of 18471240 is 4217481.

It can be written as a sum of positive squares in 2 ways, for example, as 18198756 + 272484 = 4266^2 + 522^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (18471241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 390 + ... + 6090.

Almost surely, 2^18471240 is an apocalyptic number.

18471240 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 18471240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31047390).

18471240 is an abundant number, since it is smaller than the sum of its proper divisors (43623540).

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

18471240 is a wasteful number, since it uses less digits than its factorization.

18471240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5724 (or 5711 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 18471240 is about 4297.8180510580. The cubic root of 18471240 is about 264.3415002068.

The spelling of 18471240 in words is "eighteen million, four hundred seventy-one thousand, two hundred forty".