284147981 has 6 divisors (see below), whose sum is σ = 307687050. Its totient is φ = 262290288.

The previous prime is 284147977. The next prime is 284147987. The reversal of 284147981 is 189741482.

It can be written as a sum of positive squares in 3 ways, for example, as 35581225 + 248566756 = 5965^2 + 15766^2 .

It is not a de Polignac number, because 284147981 - 2² = 284147977 is a prime.

It is a super-2 number, since 2×284147981² = 161480150212752722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (284147987) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 840506 + ... + 840843.

It is an arithmetic number, because the mean of its divisors is an integer number (51281175).

Almost surely, 2^284147981 is an apocalyptic number.

It is an amenable number.

284147981 is a deficient number, since it is larger than the sum of its proper divisors (23539069).

284147981 is a wasteful number, since it uses less digits than its factorization.

284147981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1681375 (or 1681362 counting only the distinct ones).

The product of its digits is 129024, while the sum is 44.

The square root of 284147981 is about 16856.6895029837. The cubic root of 284147981 is about 657.4279919406.

The spelling of 284147981 in words is "two hundred eighty-four million, one hundred forty-seven thousand, nine hundred eighty-one".