287971440 has 80 divisors (see below), whose sum is σ = 897481248. Its totient is φ = 76382208.

The previous prime is 287971433. The next prime is 287971451. The reversal of 287971440 is 44179782.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 287971392 and 287971401.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43212 + ... + 49428.

Almost surely, 2^287971440 is an apocalyptic number.

287971440 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 287971440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (448740624).

287971440 is an abundant number, since it is smaller than the sum of its proper divisors (609509808).

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

287971440 is a wasteful number, since it uses less digits than its factorization.

287971440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6426 (or 6420 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 42.

The square root of 287971440 is about 16969.7212705454. The cubic root of 287971440 is about 660.3636196494.

The spelling of 287971440 in words is "two hundred eighty-seven million, nine hundred seventy-one thousand, four hundred forty".