198522421 has 4 divisors (see below), whose sum is σ = 200753100. Its totient is φ = 196291744.

The previous prime is 198522409. The next prime is 198522449. The reversal of 198522421 is 124225891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 36469521 + 162052900 = 6039^2 + 12730^2 .

It is a cyclic number.

It is not a de Polignac number, because 198522421 - 2⁷ = 198522293 is a prime.

It is a super-2 number, since 2×198522421² = 78822303279402482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198522491) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1115206 + ... + 1115383.

It is an arithmetic number, because the mean of its divisors is an integer number (50188275).

Almost surely, 2^198522421 is an apocalyptic number.

It is an amenable number.

198522421 is a deficient number, since it is larger than the sum of its proper divisors (2230679).

198522421 is an equidigital number, since it uses as much as digits as its factorization.

198522421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2230678.

The product of its digits is 11520, while the sum is 34.

The square root of 198522421 is about 14089.7984726539. The cubic root of 198522421 is about 583.3598307057.

The spelling of 198522421 in words is "one hundred ninety-eight million, five hundred twenty-two thousand, four hundred twenty-one".