206698438881 has 81 divisors (see below), whose sum is σ = 343636593937. Its totient is φ = 119625139920.

The previous prime is 206698438879. The next prime is 206698438987. The reversal of 206698438881 is 188834896602.

The square root of 206698438881 is 454641.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 206698438881 - 2¹ = 206698438879 is a prime.

It is a super-2 number, since 2×206698438881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206698438801) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 345072220 + ... + 345072818.

Almost surely, 2^206698438881 is an apocalyptic number.

206698438881 is the 454641-st square number.

206698438881 is the 227321-st centered octagonal number.

It is an amenable number.

206698438881 is a deficient number, since it is larger than the sum of its proper divisors (136938155056).

206698438881 is an equidigital number, since it uses as much as digits as its factorization.

206698438881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1272 (or 636 counting only the distinct ones).

The product of its (nonzero) digits is 31850496, while the sum is 63.

The spelling of 206698438881 in words is "two hundred six billion, six hundred ninety-eight million, four hundred thirty-eight thousand, eight hundred eighty-one".