85705921 has 8 divisors (see below), whose sum is σ = 98103104. Its totient is φ = 73347120.

The previous prime is 85705909. The next prime is 85705987. The reversal of 85705921 is 12950758.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 85705921 - 2¹¹ = 85703873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85705901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4635 + ... + 13888.

It is an arithmetic number, because the mean of its divisors is an integer number (12262888).

Almost surely, 2^85705921 is an apocalyptic number.

It is an amenable number.

85705921 is a deficient number, since it is larger than the sum of its proper divisors (12397183).

85705921 is a wasteful number, since it uses less digits than its factorization.

85705921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19191.

The product of its (nonzero) digits is 25200, while the sum is 37.

The square root of 85705921 is about 9257.7492405012. The cubic root of 85705921 is about 440.8967952474.

The spelling of 85705921 in words is "eighty-five million, seven hundred five thousand, nine hundred twenty-one".