205253051621 has 8 divisors (see below), whose sum is σ = 208181570688. Its totient is φ = 202325578000.

The previous prime is 205253051603. The next prime is 205253051651. The reversal of 205253051621 is 126150352502.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205253051621 is a prime.

It is a super-3 number, since 3×205253051621³ (a number of 35 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205253051651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 138431 + ... + 655491.

It is an arithmetic number, because the mean of its divisors is an integer number (26022696336).

Almost surely, 2^205253051621 is an apocalyptic number.

It is an amenable number.

205253051621 is a deficient number, since it is larger than the sum of its proper divisors (2928519067).

205253051621 is an equidigital number, since it uses as much as digits as its factorization.

205253051621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522723.

The product of its (nonzero) digits is 18000, while the sum is 32.

The spelling of 205253051621 in words is "two hundred five billion, two hundred fifty-three million, fifty-one thousand, six hundred twenty-one".