198138730 has 32 divisors (see below), whose sum is σ = 370092240. Its totient is φ = 76285440.

The previous prime is 198138683. The next prime is 198138739. The reversal of 198138730 is 37831891.

It can be written as a sum of positive squares in 8 ways, for example, as 128799801 + 69338929 = 11349^2 + 8327^2 .

It is a super-3 number, since 3×198138730³ (a number of 26 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (198138739) 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, 114270 + ... + 115990.

Almost surely, 2^198138730 is an apocalyptic number.

198138730 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

198138730 is a deficient number, since it is larger than the sum of its proper divisors (171953510).

198138730 is a wasteful number, since it uses less digits than its factorization.

198138730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2154.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 198138730 is about 14076.1759721879. The cubic root of 198138730 is about 582.9837618937.

The spelling of 198138730 in words is "one hundred ninety-eight million, one hundred thirty-eight thousand, seven hundred thirty".