85503211721 has 2 divisors, whose sum is σ = 85503211722. Its totient is φ = 85503211720.

The previous prime is 85503211711. The next prime is 85503211723. The reversal of 85503211721 is 12711230558.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63498456121 + 22004755600 = 251989^2 + 148340^2 .

It is a cyclic number.

It is not a de Polignac number, because 85503211721 - 2³⁴ = 68323342537 is a prime.

Together with 85503211723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (85503211723) 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, 42751605860 + 42751605861.

It is an arithmetic number, because the mean of its divisors is an integer number (42751605861).

Almost surely, 2^85503211721 is an apocalyptic number.

It is an amenable number.

85503211721 is a deficient number, since it is larger than the sum of its proper divisors (1).

85503211721 is an equidigital number, since it uses as much as digits as its factorization.

85503211721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16800, while the sum is 35.

The spelling of 85503211721 in words is "eighty-five billion, five hundred three million, two hundred eleven thousand, seven hundred twenty-one".