19404918 has 36 divisors (see below), whose sum is σ = 45534060. Its totient is φ = 5969808.

The previous prime is 19404907. The next prime is 19404919. The reversal of 19404918 is 81940491.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19404919) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 148 + ... + 6231.

It is an arithmetic number, because the mean of its divisors is an integer number (1264835).

Almost surely, 2^19404918 is an apocalyptic number.

19404918 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19404918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22767030).

19404918 is an abundant number, since it is smaller than the sum of its proper divisors (26129142).

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

19404918 is a wasteful number, since it uses less digits than its factorization.

19404918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6413 (or 6397 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 19404918 is about 4405.1013609224. The cubic root of 19404918 is about 268.7224418831.

The spelling of 19404918 in words is "nineteen million, four hundred four thousand, nine hundred eighteen".