206645540 has 48 divisors (see below), whose sum is σ = 464713200. Its totient is φ = 76910592.

The previous prime is 206645533. The next prime is 206645563. The reversal of 206645540 is 45546602.

It can be written as a sum of positive squares in 8 ways, for example, as 952576 + 205692964 = 976^2 + 14342^2 .

It is a junction number, because it is equal to n+sod(n) for n = 206645497 and 206645506.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26846 + ... + 33674.

It is an arithmetic number, because the mean of its divisors is an integer number (9681525).

Almost surely, 2^206645540 is an apocalyptic number.

206645540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 206645540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232356600).

206645540 is an abundant number, since it is smaller than the sum of its proper divisors (258067660).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

206645540 is a wasteful number, since it uses less digits than its factorization.

206645540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6944 (or 6942 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 32.

The square root of 206645540 is about 14375.1709555052. The cubic root of 206645540 is about 591.2103278421.

The spelling of 206645540 in words is "two hundred six million, six hundred forty-five thousand, five hundred forty".