205221015 has 12 divisors (see below), whose sum is σ = 355716504. Its totient is φ = 109451184.

The previous prime is 205221001. The next prime is 205221017. The reversal of 205221015 is 510122502.

It is not a de Polignac number, because 205221015 - 2⁴ = 205220999 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205221017) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2280189 + ... + 2280278.

It is an arithmetic number, because the mean of its divisors is an integer number (29643042).

Almost surely, 2^205221015 is an apocalyptic number.

205221015 is a deficient number, since it is larger than the sum of its proper divisors (150495489).

205221015 is a wasteful number, since it uses less digits than its factorization.

205221015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4560478 (or 4560475 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 205221015 is about 14325.5371627035. The cubic root of 205221015 is about 589.8486780364.

Adding to 205221015 its reverse (510122502), we get a palindrome (715343517).

The spelling of 205221015 in words is "two hundred five million, two hundred twenty-one thousand, fifteen".