287864505 has 12 divisors (see below), whose sum is σ = 498965220. Its totient is φ = 153527712.

The previous prime is 287864491. The next prime is 287864513. The reversal of 287864505 is 505468782.

287864505 is a `hidden beast` number, since 2 + 87 + 8 + 64 + 505 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 125148969 + 162715536 = 11187^2 + 12756^2 .

It is not a de Polignac number, because 287864505 - 2¹⁵ = 287831737 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 6396989 = 287864505 / (2 + 8 + 7 + 8 + 6 + 4 + 5 + 0 + 5).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3198450 + ... + 3198539.

It is an arithmetic number, because the mean of its divisors is an integer number (41580435).

Almost surely, 2^287864505 is an apocalyptic number.

It is an amenable number.

287864505 is a deficient number, since it is larger than the sum of its proper divisors (211100715).

287864505 is a wasteful number, since it uses less digits than its factorization.

287864505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6397000 (or 6396997 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The square root of 287864505 is about 16966.5702191103. The cubic root of 287864505 is about 660.2818699612.

It can be divided in two parts, 287864 and 505, that added together give a square (288369 = 537²).

The spelling of 287864505 in words is "two hundred eighty-seven million, eight hundred sixty-four thousand, five hundred five".