84784621 has 2 divisors, whose sum is σ = 84784622. Its totient is φ = 84784620.

The previous prime is 84784619. The next prime is 84784697. The reversal of 84784621 is 12648748.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43375396 + 41409225 = 6586^2 + 6435^2 .

It is a cyclic number.

It is not a de Polignac number, because 84784621 - 2¹ = 84784619 is a prime.

It is a super-2 number, since 2×84784621² = 14376863916227282, which contains 22 as substring.

Together with 84784619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84784421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42392310 + 42392311.

It is an arithmetic number, because the mean of its divisors is an integer number (42392311).

Almost surely, 2^84784621 is an apocalyptic number.

It is an amenable number.

84784621 is a deficient number, since it is larger than the sum of its proper divisors (1).

84784621 is an equidigital number, since it uses as much as digits as its factorization.

84784621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86016, while the sum is 40.

The square root of 84784621 is about 9207.8564823742. The cubic root of 84784621 is about 439.3112865290.

The spelling of 84784621 in words is "eighty-four million, seven hundred eighty-four thousand, six hundred twenty-one".