84117281 has 4 divisors (see below), whose sum is σ = 86168964. Its totient is φ = 82065600.

The previous prime is 84117277. The next prime is 84117289. The reversal of 84117281 is 18271148.

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 40768225 + 43349056 = 6385^2 + 6584^2 .

It is not a de Polignac number, because 84117281 - 2² = 84117277 is a prime.

It is a super-2 number, since 2×84117281² = 14151433925665922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84117289) 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, 1025780 + ... + 1025861.

It is an arithmetic number, because the mean of its divisors is an integer number (21542241).

Almost surely, 2^84117281 is an apocalyptic number.

It is an amenable number.

84117281 is a deficient number, since it is larger than the sum of its proper divisors (2051683).

84117281 is a wasteful number, since it uses less digits than its factorization.

84117281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2051682.

The product of its digits is 3584, while the sum is 32.

The square root of 84117281 is about 9171.5473612690. The cubic root of 84117281 is about 438.1556423712.

The spelling of 84117281 in words is "eighty-four million, one hundred seventeen thousand, two hundred eighty-one".