206534640 has 160 divisors (see below), whose sum is σ = 703080000. Its totient is φ = 49840128.

The previous prime is 206534611. The next prime is 206534659. The reversal of 206534640 is 46435602.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 206534598 and 206534607.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 164736 + ... + 165984.

It is an arithmetic number, because the mean of its divisors is an integer number (4394250).

Almost surely, 2^206534640 is an apocalyptic number.

206534640 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 206534640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (351540000).

206534640 is an abundant number, since it is smaller than the sum of its proper divisors (496545360).

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

206534640 is a wasteful number, since it uses less digits than its factorization.

206534640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1331 (or 1325 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 206534640 is about 14371.3130924074. The cubic root of 206534640 is about 591.1045477419.

The spelling of 206534640 in words is "two hundred six million, five hundred thirty-four thousand, six hundred forty".