85312720781 has 16 divisors (see below), whose sum is σ = 94448816640. Its totient is φ = 76739607360.

The previous prime is 85312720741. The next prime is 85312720873. The reversal of 85312720781 is 18702721358.

It is not a de Polignac number, because 85312720781 - 2¹⁰ = 85312719757 is a prime.

It is a super-2 number, since 2×85312720781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85312720741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1335230 + ... + 1397663.

It is an arithmetic number, because the mean of its divisors is an integer number (5903051040).

Almost surely, 2^85312720781 is an apocalyptic number.

It is an amenable number.

85312720781 is a deficient number, since it is larger than the sum of its proper divisors (9136095859).

85312720781 is a wasteful number, since it uses less digits than its factorization.

85312720781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2732996.

The product of its (nonzero) digits is 188160, while the sum is 44.

The spelling of 85312720781 in words is "eighty-five billion, three hundred twelve million, seven hundred twenty thousand, seven hundred eighty-one".