206421081 has 8 divisors (see below), whose sum is σ = 276917280. Its totient is φ = 136769472.

The previous prime is 206421053. The next prime is 206421119. The reversal of 206421081 is 180124602.

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

It is not a de Polignac number, because 206421081 - 2²² = 202226777 is a prime.

It is a super-2 number, since 2×206421081² = 85219325362417122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (206421181) 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, 210576 + ... + 211553.

It is an arithmetic number, because the mean of its divisors is an integer number (34614660).

Almost surely, 2^206421081 is an apocalyptic number.

It is an amenable number.

206421081 is a deficient number, since it is larger than the sum of its proper divisors (70496199).

206421081 is a wasteful number, since it uses less digits than its factorization.

206421081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422295.

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 206421081 is about 14367.3616575904. The cubic root of 206421081 is about 590.9961921531.

Adding to 206421081 its reverse (180124602), we get a palindrome (386545683).

The spelling of 206421081 in words is "two hundred six million, four hundred twenty-one thousand, eighty-one".