198725409 has 27 divisors (see below), whose sum is σ = 297356787. Its totient is φ = 127887984.

The previous prime is 198725399. The next prime is 198725411. The reversal of 198725409 is 904527891.

The square root of 198725409 is 14097.

It is a perfect power (a square), and thus also a powerful number.

198725409 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 177822225 + 20903184 = 13335^2 + 4572^2 .

It is not a de Polignac number, because 198725409 - 2⁷ = 198725281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (198725809) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1564704 + ... + 1564830.

Almost surely, 2^198725409 is an apocalyptic number.

198725409 is the 14097-th square number.

198725409 is the 7049-th centered octagonal number.

It is an amenable number.

198725409 is a deficient number, since it is larger than the sum of its proper divisors (98631378).

198725409 is an equidigital number, since it uses as much as digits as its factorization.

198725409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334 (or 167 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The cubic root of 198725409 is about 583.5585903018.

It can be divided in two parts, 19872 and 5409, that added together give a square (25281 = 159²).

The spelling of 198725409 in words is "one hundred ninety-eight million, seven hundred twenty-five thousand, four hundred nine".