205020421331 has 4 divisors (see below), whose sum is σ = 223658641464. Its totient is φ = 186382201200.

The previous prime is 205020421301. The next prime is 205020421337. The reversal of 205020421331 is 133124020502.

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

It is a cyclic number.

It is not a de Polignac number, because 205020421331 - 2¹⁴ = 205020404947 is a prime.

It is a super-2 number, since 2×205020421331² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205020421297 and 205020421306.

It is not an unprimeable number, because it can be changed into a prime (205020421337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9319110050 + ... + 9319110071.

It is an arithmetic number, because the mean of its divisors is an integer number (55914660366).

Almost surely, 2^205020421331 is an apocalyptic number.

205020421331 is a deficient number, since it is larger than the sum of its proper divisors (18638220133).

205020421331 is a wasteful number, since it uses less digits than its factorization.

205020421331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18638220132.

The product of its (nonzero) digits is 1440, while the sum is 23.

Adding to 205020421331 its reverse (133124020502), we get a palindrome (338144441833).

The spelling of 205020421331 in words is "two hundred five billion, twenty million, four hundred twenty-one thousand, three hundred thirty-one".