84661281 has 40 divisors (see below), whose sum is σ = 131183360. Its totient is φ = 54377568.

The previous prime is 84661277. The next prime is 84661301. The reversal of 84661281 is 18216648.

It is not a de Polignac number, because 84661281 - 2² = 84661277 is a prime.

It is a super-2 number, since 2×84661281² = 14335065001121922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84661201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 379536 + ... + 379758.

It is an arithmetic number, because the mean of its divisors is an integer number (3279584).

Almost surely, 2^84661281 is an apocalyptic number.

84661281 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

84661281 is a deficient number, since it is larger than the sum of its proper divisors (46522079).

84661281 is a wasteful number, since it uses less digits than its factorization.

84661281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387 (or 378 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 84661281 is about 9201.1565033967. The cubic root of 84661281 is about 439.0981545181.

The spelling of 84661281 in words is "eighty-four million, six hundred sixty-one thousand, two hundred eighty-one".