287689920 has 224 divisors, whose sum is σ = 1078358016. Its totient is φ = 63590400.

The previous prime is 287689903. The next prime is 287689931. The reversal of 287689920 is 29986782.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-4 number, since 4×287689920⁴ (a number of 35 digits) contains 4444 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 207630 + ... + 209010.

Almost surely, 2^287689920 is an apocalyptic number.

287689920 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 287689920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (539179008).

287689920 is an abundant number, since it is smaller than the sum of its proper divisors (790668096).

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

287689920 is a wasteful number, since it uses less digits than its factorization.

287689920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1439 (or 1429 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 51.

The square root of 287689920 is about 16961.4244684814. The cubic root of 287689920 is about 660.1483596692.

The spelling of 287689920 in words is "two hundred eighty-seven million, six hundred eighty-nine thousand, nine hundred twenty".