19918080 has 432 divisors, whose sum is σ = 89281920. Its totient is φ = 3981312.

The previous prime is 19918057. The next prime is 19918081. The reversal of 19918080 is 8081991.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19918081) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1048311 + ... + 1048329.

Almost surely, 2^19918080 is an apocalyptic number.

19918080 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 19918080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44640960).

19918080 is an abundant number, since it is smaller than the sum of its proper divisors (69363840).

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

19918080 is a wasteful number, since it uses less digits than its factorization.

19918080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66 (or 49 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 19918080 is about 4462.9676225579. The cubic root of 19918080 is about 271.0706460155.

The spelling of 19918080 in words is "nineteen million, nine hundred eighteen thousand, eighty".