84818336851921 has 2 divisors, whose sum is σ = 84818336851922. Its totient is φ = 84818336851920.

The previous prime is 84818336851907. The next prime is 84818336851931. The reversal of 84818336851921 is 12915863381848.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 82481107411921 + 2337229440000 = 9081911^2 + 1528800^2 .

It is a cyclic number.

It is not a de Polignac number, because 84818336851921 - 2¹³ = 84818336843729 is a prime.

It is not a weakly prime, because it can be changed into another prime (84818336851931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42409168425960 + 42409168425961.

It is an arithmetic number, because the mean of its divisors is an integer number (42409168425961).

Almost surely, 2^{84818336851921} is an apocalyptic number.

It is an amenable number.

84818336851921 is a deficient number, since it is larger than the sum of its proper divisors (1).

84818336851921 is an equidigital number, since it uses as much as digits as its factorization.

84818336851921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 79626240, while the sum is 67.

The spelling of 84818336851921 in words is "eighty-four trillion, eight hundred eighteen billion, three hundred thirty-six million, eight hundred fifty-one thousand, nine hundred twenty-one".