287408861 has 4 divisors (see below), whose sum is σ = 294092832. Its totient is φ = 280724892.

The previous prime is 287408819. The next prime is 287408899. The reversal of 287408861 is 168804782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 287408861 - 2²⁶ = 220299997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (287404861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3341921 + ... + 3342006.

It is an arithmetic number, because the mean of its divisors is an integer number (73523208).

Almost surely, 2^287408861 is an apocalyptic number.

It is an amenable number.

287408861 is a deficient number, since it is larger than the sum of its proper divisors (6683971).

287408861 is an equidigital number, since it uses as much as digits as its factorization.

287408861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6683970.

The product of its (nonzero) digits is 172032, while the sum is 44.

The square root of 287408861 is about 16953.1372022998. The cubic root of 287408861 is about 659.9333120559.

The spelling of 287408861 in words is "two hundred eighty-seven million, four hundred eight thousand, eight hundred sixty-one".