85721875729 has 4 divisors (see below), whose sum is σ = 97967857984. Its totient is φ = 73475893476.

The previous prime is 85721875717. The next prime is 85721875741. The reversal of 85721875729 is 92757812758.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (85721875717) and next prime (85721875741).

It is a cyclic number.

It is not a de Polignac number, because 85721875729 - 2⁷ = 85721875601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85721875529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6122991117 + ... + 6122991130.

It is an arithmetic number, because the mean of its divisors is an integer number (24491964496).

Almost surely, 2^85721875729 is an apocalyptic number.

It is an amenable number.

85721875729 is a deficient number, since it is larger than the sum of its proper divisors (12245982255).

85721875729 is a wasteful number, since it uses less digits than its factorization.

85721875729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12245982254.

The product of its digits is 19756800, while the sum is 61.

The spelling of 85721875729 in words is "eighty-five billion, seven hundred twenty-one million, eight hundred seventy-five thousand, seven hundred twenty-nine".