648398189 has 4 divisors (see below), whose sum is σ = 652376256. Its totient is φ = 644420124.

The previous prime is 648398183. The next prime is 648398203. The reversal of 648398189 is 981893846.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 648398189 - 2¹⁶ = 648332653 is a prime.

It is a super-2 number, since 2×648398189² = 840840422996959442, 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 (648398183) 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, 1988789 + ... + 1989114.

It is an arithmetic number, because the mean of its divisors is an integer number (163094064).

Almost surely, 2^648398189 is an apocalyptic number.

It is an amenable number.

648398189 is a deficient number, since it is larger than the sum of its proper divisors (3978067).

648398189 is a wasteful number, since it uses less digits than its factorization.

648398189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3978066.

The product of its digits is 2985984, while the sum is 56.

The square root of 648398189 is about 25463.6640921922. The cubic root of 648398189 is about 865.5269552471.

The spelling of 648398189 in words is "six hundred forty-eight million, three hundred ninety-eight thousand, one hundred eighty-nine".