195420021 has 4 divisors (see below), whose sum is σ = 260560032. Its totient is φ = 130280012.

The previous prime is 195420013. The next prime is 195420047. The reversal of 195420021 is 120024591.

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 195420021 - 2³ = 195420013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 195419973 and 195420000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195420011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32570001 + ... + 32570006.

It is an arithmetic number, because the mean of its divisors is an integer number (65140008).

Almost surely, 2^195420021 is an apocalyptic number.

It is an amenable number.

195420021 is a deficient number, since it is larger than the sum of its proper divisors (65140011).

195420021 is an equidigital number, since it uses as much as digits as its factorization.

195420021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65140010.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 195420021 is about 13979.2711183380. The cubic root of 195420021 is about 580.3050525687.

The spelling of 195420021 in words is "one hundred ninety-five million, four hundred twenty thousand, twenty-one".