287987091 has 16 divisors (see below), whose sum is σ = 439219200. Its totient is φ = 164420928.

The previous prime is 287987087. The next prime is 287987101. The reversal of 287987091 is 190789782.

It is not a de Polignac number, because 287987091 - 2² = 287987087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (287987041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21750 + ... + 32388.

It is an arithmetic number, because the mean of its divisors is an integer number (27451200).

Almost surely, 2^287987091 is an apocalyptic number.

287987091 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

287987091 is a deficient number, since it is larger than the sum of its proper divisors (151232109).

287987091 is a wasteful number, since it uses less digits than its factorization.

287987091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11938.

The product of its (nonzero) digits is 508032, while the sum is 51.

The square root of 287987091 is about 16970.1824091552. The cubic root of 287987091 is about 660.3755828308.

The spelling of 287987091 in words is "two hundred eighty-seven million, nine hundred eighty-seven thousand, ninety-one".