206021881 has 16 divisors (see below), whose sum is σ = 225086400. Its totient is φ = 187437888.

The previous prime is 206021873. The next prime is 206021891. The reversal of 206021881 is 188120602.

It is a cyclic number.

It is not a de Polignac number, because 206021881 - 2³ = 206021873 is a prime.

It is a super-2 number, since 2×206021881² = 84890030901556322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206021801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 491490 + ... + 491908.

It is an arithmetic number, because the mean of its divisors is an integer number (14067900).

Almost surely, 2^206021881 is an apocalyptic number.

It is an amenable number.

206021881 is a deficient number, since it is larger than the sum of its proper divisors (19064519).

206021881 is a wasteful number, since it uses less digits than its factorization.

206021881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888.

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 206021881 is about 14353.4623349211. The cubic root of 206021881 is about 590.6149682833.

The spelling of 206021881 in words is "two hundred six million, twenty-one thousand, eight hundred eighty-one".