205143643 has 8 divisors (see below), whose sum is σ = 206320608. Its totient is φ = 203970624.

The previous prime is 205143629. The next prime is 205143667. The reversal of 205143643 is 346341502.

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 205143643 - 2⁵ = 205143611 is a prime.

It is a super-2 number, since 2×205143643² = 84167828526622898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205143343) 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, 202005 + ... + 203017.

It is an arithmetic number, because the mean of its divisors is an integer number (25790076).

Almost surely, 2^205143643 is an apocalyptic number.

205143643 is a deficient number, since it is larger than the sum of its proper divisors (1176965).

205143643 is a wasteful number, since it uses less digits than its factorization.

205143643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1973.

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 205143643 is about 14322.8364160176. The cubic root of 205143643 is about 589.7745408782.

The spelling of 205143643 in words is "two hundred five million, one hundred forty-three thousand, six hundred forty-three".