205006621 has 8 divisors (see below), whose sum is σ = 221685120. Its totient is φ = 188841408.

The previous prime is 205006583. The next prime is 205006631. The reversal of 205006621 is 126600502.

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 205006621 - 2¹¹ = 205004573 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205006592 and 205006601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205006631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127491 + ... + 129088.

It is an arithmetic number, because the mean of its divisors is an integer number (27710640).

Almost surely, 2^205006621 is an apocalyptic number.

It is an amenable number.

205006621 is a deficient number, since it is larger than the sum of its proper divisors (16678499).

205006621 is a wasteful number, since it uses less digits than its factorization.

205006621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256643.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 205006621 is about 14318.0522767589. The cubic root of 205006621 is about 589.6432018728.

The spelling of 205006621 in words is "two hundred five million, six thousand, six hundred twenty-one".