288900021 has 4 divisors (see below), whose sum is σ = 385200032. Its totient is φ = 192600012.

The previous prime is 288900019. The next prime is 288900043. The reversal of 288900021 is 120009882.

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 not a de Polignac number, because 288900021 - 2¹ = 288900019 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 (288900071) 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 3 ways as a sum of consecutive naturals, for example, 48150001 + ... + 48150006.

It is an arithmetic number, because the mean of its divisors is an integer number (96300008).

Almost surely, 2^288900021 is an apocalyptic number.

It is an amenable number.

288900021 is a deficient number, since it is larger than the sum of its proper divisors (96300011).

288900021 is an equidigital number, since it uses as much as digits as its factorization.

288900021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96300010.

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 288900021 is about 16997.0591868123. The cubic root of 288900021 is about 661.0726519842.

The spelling of 288900021 in words is "two hundred eighty-eight million, nine hundred thousand, twenty-one".