206555638 has 16 divisors (see below), whose sum is σ = 317720736. Its totient is φ = 100679040.

The previous prime is 206555633. The next prime is 206555639. The reversal of 206555638 is 836555602.

It is a self number, because there is not a number n which added to its sum of digits gives 206555638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206555633) 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, 6295 + ... + 21277.

It is an arithmetic number, because the mean of its divisors is an integer number (19857546).

Almost surely, 2^206555638 is an apocalyptic number.

206555638 is a deficient number, since it is larger than the sum of its proper divisors (111165098).

206555638 is a wasteful number, since it uses less digits than its factorization.

206555638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15159.

The product of its (nonzero) digits is 216000, while the sum is 40.

The square root of 206555638 is about 14372.0436264298. The cubic root of 206555638 is about 591.1245792367.

The spelling of 206555638 in words is "two hundred six million, five hundred fifty-five thousand, six hundred thirty-eight".