84776621 has 2 divisors, whose sum is σ = 84776622. Its totient is φ = 84776620.

The previous prime is 84776617. The next prime is 84776623. The reversal of 84776621 is 12667748.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60668521 + 24108100 = 7789^2 + 4910^2 .

It is a cyclic number.

It is not a de Polignac number, because 84776621 - 2² = 84776617 is a prime.

It is a Sophie Germain prime.

Together with 84776623, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84776623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42388310 + 42388311.

It is an arithmetic number, because the mean of its divisors is an integer number (42388311).

Almost surely, 2^84776621 is an apocalyptic number.

It is an amenable number.

84776621 is a deficient number, since it is larger than the sum of its proper divisors (1).

84776621 is an equidigital number, since it uses as much as digits as its factorization.

84776621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 41.

The square root of 84776621 is about 9207.4220604901. The cubic root of 84776621 is about 439.2974687682.

The spelling of 84776621 in words is "eighty-four million, seven hundred seventy-six thousand, six hundred twenty-one".