85143967621 has 2 divisors, whose sum is σ = 85143967622. Its totient is φ = 85143967620.

The previous prime is 85143967619. The next prime is 85143967627. The reversal of 85143967621 is 12676934158.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 82346615521 + 2797352100 = 286961^2 + 52890^2 .

It is a cyclic number.

It is not a de Polignac number, because 85143967621 - 2¹ = 85143967619 is a prime.

Together with 85143967619, 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 (85143967627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42571983810 + 42571983811.

It is an arithmetic number, because the mean of its divisors is an integer number (42571983811).

Almost surely, 2^85143967621 is an apocalyptic number.

It is an amenable number.

85143967621 is a deficient number, since it is larger than the sum of its proper divisors (1).

85143967621 is an equidigital number, since it uses as much as digits as its factorization.

85143967621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 52.

The spelling of 85143967621 in words is "eighty-five billion, one hundred forty-three million, nine hundred sixty-seven thousand, six hundred twenty-one".