19990118400 has 612 divisors, whose sum is σ = 77818425552. Its totient is φ = 4514119680.

The previous prime is 19990118387. The next prime is 19990118437. The reversal of 19990118400 is 481109991.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 240844759 + ... + 240844841.

Almost surely, 2^19990118400 is an apocalyptic number.

19990118400 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 19990118400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38909212776).

19990118400 is an abundant number, since it is smaller than the sum of its proper divisors (57828307152).

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

19990118400 is an frugal number, since it uses more digits than its factorization.

19990118400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 42.

The spelling of 19990118400 in words is "nineteen billion, nine hundred ninety million, one hundred eighteen thousand, four hundred".