85768985981 has 54 divisors (see below), whose sum is σ = 105916422906. Its totient is φ = 69239016000.

The previous prime is 85768985971. The next prime is 85768986013. The reversal of 85768985981 is 18958986758.

It can be written as a sum of positive squares in 3 ways, for example, as 2592100 + 85766393881 = 1610^2 + 292859^2 .

It is a de Polignac number, because none of the positive numbers 2^k-85768985981 is a prime.

It is a super-2 number, since 2×85768985981² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 85768985899 and 85768985908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85768985971) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 473861711 + ... + 473861891.

It is an arithmetic number, because the mean of its divisors is an integer number (1961415239).

Almost surely, 2^85768985981 is an apocalyptic number.

It is an amenable number.

85768985981 is a deficient number, since it is larger than the sum of its proper divisors (20147436925).

85768985981 is a wasteful number, since it uses less digits than its factorization.

85768985981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523 (or 312 counting only the distinct ones).

The product of its digits is 348364800, while the sum is 74.

The spelling of 85768985981 in words is "eighty-five billion, seven hundred sixty-eight million, nine hundred eighty-five thousand, nine hundred eighty-one".