284240021 has 4 divisors (see below), whose sum is σ = 306104652. Its totient is φ = 262375392.

The previous prime is 284239997. The next prime is 284240029. The reversal of 284240021 is 120042482.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 46771921 + 237468100 = 6839^2 + 15410^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-284240021 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 (284240029) 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, 10932296 + ... + 10932321.

It is an arithmetic number, because the mean of its divisors is an integer number (76526163).

Almost surely, 2^284240021 is an apocalyptic number.

It is an amenable number.

284240021 is a deficient number, since it is larger than the sum of its proper divisors (21864631).

284240021 is a wasteful number, since it uses less digits than its factorization.

284240021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21864630.

The product of its (nonzero) digits is 1024, while the sum is 23.

The square root of 284240021 is about 16859.4193553633. The cubic root of 284240021 is about 657.4989680332.

The spelling of 284240021 in words is "two hundred eighty-four million, two hundred forty thousand, twenty-one".