286621920 has 288 divisors, whose sum is σ = 1074868704. Its totient is φ = 69120000.

The previous prime is 286621903. The next prime is 286621927. The reversal of 286621920 is 29126682.

It is a happy number.

286621920 is a `hidden beast` number, since 2 + 8 + 6 + 621 + 9 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (286621927) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1141795 + ... + 1142045.

It is an arithmetic number, because the mean of its divisors is an integer number (3732183).

Almost surely, 2^286621920 is an apocalyptic number.

286621920 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 286621920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (537434352).

286621920 is an abundant number, since it is smaller than the sum of its proper divisors (788246784).

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

286621920 is a wasteful number, since it uses less digits than its factorization.

286621920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346 (or 335 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 286621920 is about 16929.9119903206. The cubic root of 286621920 is about 659.3304504690.

The spelling of 286621920 in words is "two hundred eighty-six million, six hundred twenty-one thousand, nine hundred twenty".