18953440 has 96 divisors (see below), whose sum is σ = 49805280. Its totient is φ = 6814720.

The previous prime is 18953437. The next prime is 18953447. The reversal of 18953440 is 4435981.

It is a nialpdrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 18953396 and 18953405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18953447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212916 + ... + 213004.

It is an arithmetic number, because the mean of its divisors is an integer number (518805).

Almost surely, 2^18953440 is an apocalyptic number.

18953440 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 18953440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24902640).

18953440 is an abundant number, since it is smaller than the sum of its proper divisors (30851840).

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

18953440 is an equidigital number, since it uses as much as digits as its factorization.

18953440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 18953440 is about 4353.5548692993. The cubic root of 18953440 is about 266.6220203033.

It can be divided in two parts, 1895 and 3440, that added together give a palindrome (5335).

The spelling of 18953440 in words is "eighteen million, nine hundred fifty-three thousand, four hundred forty".