205070921 has 24 divisors (see below), whose sum is σ = 242898432. Its totient is φ = 172497600.

The previous prime is 205070911. The next prime is 205070927. The reversal of 205070921 is 129070502.

It is not a de Polignac number, because 205070921 - 2²² = 200876617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205070927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 85085 + ... + 87461.

It is an arithmetic number, because the mean of its divisors is an integer number (10120768).

Almost surely, 2^205070921 is an apocalyptic number.

It is an amenable number.

205070921 is a deficient number, since it is larger than the sum of its proper divisors (37827511).

205070921 is a wasteful number, since it uses less digits than its factorization.

205070921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2453 (or 2442 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 205070921 is about 14320.2975178590. The cubic root of 205070921 is about 589.7048423123.

The spelling of 205070921 in words is "two hundred five million, seventy thousand, nine hundred twenty-one".