206809021429920 has 2304 divisors, whose sum is σ = 903367430784000. Its totient is φ = 42799541944320.

The previous prime is 206809021429897. The next prime is 206809021429931. The reversal of 206809021429920 is 29924120908602.

It is a happy number.

206809021429920 is a `hidden beast` number, since 20 + 6 + 8 + 0 + 90 + 21 + 429 + 92 + 0 = 666.

It is a super-2 number, since 2×206809021429920² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 242449028214 + ... + 242449029066.

It is an arithmetic number, because the mean of its divisors is an integer number (392086558500).

Almost surely, 2^{206809021429920} is an apocalyptic number.

206809021429920 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 206809021429920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (451683715392000).

206809021429920 is an abundant number, since it is smaller than the sum of its proper divisors (696558409354080).

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

206809021429920 is a wasteful number, since it uses less digits than its factorization.

206809021429920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1588 (or 1563 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 206809021429920 in words is "two hundred six trillion, eight hundred nine billion, twenty-one million, four hundred twenty-nine thousand, nine hundred twenty".