287491680 has 240 divisors, whose sum is σ = 1159915680. Its totient is φ = 65691648.

The previous prime is 287491661. The next prime is 287491691. The reversal of 287491680 is 86194782.

287491680 is a `hidden beast` number, since 2 + 87 + 491 + 6 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 89136 + ... + 92304.

It is an arithmetic number, because the mean of its divisors is an integer number (4832982).

Almost surely, 2^287491680 is an apocalyptic number.

287491680 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 287491680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (579957840).

287491680 is an abundant number, since it is smaller than the sum of its proper divisors (872424000).

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

287491680 is a wasteful number, since it uses less digits than its factorization.

287491680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3203 (or 3186 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 287491680 is about 16955.5796126231. The cubic root of 287491680 is about 659.9966941983.

The spelling of 287491680 in words is "two hundred eighty-seven million, four hundred ninety-one thousand, six hundred eighty".