206391900 has 288 divisors, whose sum is σ = 745452288. Its totient is φ = 43315200.

The previous prime is 206391877. The next prime is 206391907. The reversal of 206391900 is 9193602.

It is a super-2 number, since 2×206391900² = 85195232771220000, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206391907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 729159 + ... + 729441.

It is an arithmetic number, because the mean of its divisors is an integer number (2588376).

Almost surely, 2^206391900 is an apocalyptic number.

206391900 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 206391900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (372726144).

206391900 is an abundant number, since it is smaller than the sum of its proper divisors (539060388).

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

206391900 is a wasteful number, since it uses less digits than its factorization.

206391900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341 (or 334 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 30.

The square root of 206391900 is about 14366.3460907776. The cubic root of 206391900 is about 590.9683418442.

The spelling of 206391900 in words is "two hundred six million, three hundred ninety-one thousand, nine hundred".