198979770 has 64 divisors (see below), whose sum is σ = 522547200. Its totient is φ = 48091200.

The previous prime is 198979769. The next prime is 198979771. The reversal of 198979770 is 77979891.

It is an interprime number because it is at equal distance from previous prime (198979769) and next prime (198979771).

It is a self number, because there is not a number n which added to its sum of digits gives 198979770.

It is not an unprimeable number, because it can be changed into a prime (198979771) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 141531 + ... + 142929.

It is an arithmetic number, because the mean of its divisors is an integer number (8164800).

Almost surely, 2^198979770 is an apocalyptic number.

198979770 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 198979770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261273600).

198979770 is an abundant number, since it is smaller than the sum of its proper divisors (323567430).

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

198979770 is a wasteful number, since it uses less digits than its factorization.

198979770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1851.

The product of its (nonzero) digits is 2000376, while the sum is 57.

The square root of 198979770 is about 14106.0189281030. The cubic root of 198979770 is about 583.8074617842.

The spelling of 198979770 in words is "one hundred ninety-eight million, nine hundred seventy-nine thousand, seven hundred seventy".