205221031 has 8 divisors (see below), whose sum is σ = 213109344. Its totient is φ = 197470080.

The previous prime is 205221017. The next prime is 205221047. The reversal of 205221031 is 130122502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 205221031 - 2⁵ = 205220999 is a prime.

It is a super-2 number, since 2×205221031² = 84231343129405922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205220996 and 205221014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205221001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31291 + ... + 37276.

It is an arithmetic number, because the mean of its divisors is an integer number (26638668).

Almost surely, 2^205221031 is an apocalyptic number.

205221031 is a deficient number, since it is larger than the sum of its proper divisors (7888313).

205221031 is an equidigital number, since it uses as much as digits as its factorization.

205221031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68681.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 205221031 is about 14325.5377211468. The cubic root of 205221031 is about 589.8486933655.

Adding to 205221031 its reverse (130122502), we get a palindrome (335343533).

The spelling of 205221031 in words is "two hundred five million, two hundred twenty-one thousand, thirty-one".