19989450 has 192 divisors, whose sum is σ = 63745920. Its totient is φ = 4561920.

The previous prime is 19989413. The next prime is 19989457. The reversal of 19989450 is 5498991.

19989450 is a `hidden beast` number, since 199 + 8 + 9 + 450 = 666.

It is a super-2 number, since 2×19989450² = 799156222605000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 19989396 and 19989405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19989457) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 298317 + ... + 298383.

It is an arithmetic number, because the mean of its divisors is an integer number (332010).

Almost surely, 2^19989450 is an apocalyptic number.

19989450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19989450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31872960).

19989450 is an abundant number, since it is smaller than the sum of its proper divisors (43756470).

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

19989450 is a wasteful number, since it uses less digits than its factorization.

19989450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 19989450 is about 4470.9562735504. The cubic root of 19989450 is about 271.3940247550.

The spelling of 19989450 in words is "nineteen million, nine hundred eighty-nine thousand, four hundred fifty".