206221131 has 12 divisors (see below), whose sum is σ = 301956408. Its totient is φ = 135597024.

The previous prime is 206221111. The next prime is 206221139. The reversal of 206221131 is 131122602.

206221131 is a `hidden beast` number, since 2 + 0 + 622 + 11 + 31 = 666.

It is not a de Polignac number, because 206221131 - 2¹⁵ = 206188363 is a prime.

It is a super-2 number, since 2×206221131² = 85054309741838322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (206221139) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 156285 + ... + 157598.

It is an arithmetic number, because the mean of its divisors is an integer number (25163034).

Almost surely, 2^206221131 is an apocalyptic number.

206221131 is a deficient number, since it is larger than the sum of its proper divisors (95735277).

206221131 is a wasteful number, since it uses less digits than its factorization.

206221131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313962 (or 313959 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 206221131 is about 14360.4014916018. The cubic root of 206221131 is about 590.8053074759.

Adding to 206221131 its reverse (131122602), we get a palindrome (337343733).

The spelling of 206221131 in words is "two hundred six million, two hundred twenty-one thousand, one hundred thirty-one".