84953679781 has 2 divisors, whose sum is σ = 84953679782. Its totient is φ = 84953679780.

The previous prime is 84953679749. The next prime is 84953679803. The reversal of 84953679781 is 18797635948.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53379943681 + 31573736100 = 231041^2 + 177690^2 .

It is a cyclic number.

It is not a de Polignac number, because 84953679781 - 2⁵ = 84953679749 is a prime.

It is a super-2 number, since 2×84953679781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84953679731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42476839890 + 42476839891.

It is an arithmetic number, because the mean of its divisors is an integer number (42476839891).

Almost surely, 2^84953679781 is an apocalyptic number.

It is an amenable number.

84953679781 is a deficient number, since it is larger than the sum of its proper divisors (1).

84953679781 is an equidigital number, since it uses as much as digits as its factorization.

84953679781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 91445760, while the sum is 67.

The spelling of 84953679781 in words is "eighty-four billion, nine hundred fifty-three million, six hundred seventy-nine thousand, seven hundred eighty-one".