198990040 has 64 divisors (see below), whose sum is σ = 475891200. Its totient is φ = 74671488.

The previous prime is 198990031. The next prime is 198990041. The reversal of 198990040 is 40099891.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 198989975 and 198990002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198990041) 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, 80097 + ... + 82543.

It is an arithmetic number, because the mean of its divisors is an integer number (7435800).

Almost surely, 2^198990040 is an apocalyptic number.

198990040 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 198990040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (237945600).

198990040 is an abundant number, since it is smaller than the sum of its proper divisors (276901160).

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

198990040 is a wasteful number, since it uses less digits than its factorization.

198990040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2584 (or 2580 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 198990040 is about 14106.3829524085. The cubic root of 198990040 is about 583.8175056854.

It can be divided in two parts, 1989 and 90040, that added together give a palindrome (92029).

The spelling of 198990040 in words is "one hundred ninety-eight million, nine hundred ninety thousand, forty".