85639731 has 8 divisors (see below), whose sum is σ = 115750800. Its totient is φ = 56310912.

The previous prime is 85639717. The next prime is 85639733. The reversal of 85639731 is 13793658.

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

It is not a de Polignac number, because 85639731 - 2⁶ = 85639667 is a prime.

It is a super-2 number, since 2×85639731² = 14668327051504722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (85639733) 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, 195306 + ... + 195743.

It is an arithmetic number, because the mean of its divisors is an integer number (14468850).

Almost surely, 2^85639731 is an apocalyptic number.

85639731 is a deficient number, since it is larger than the sum of its proper divisors (30111069).

85639731 is a wasteful number, since it uses less digits than its factorization.

85639731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391125.

The product of its digits is 136080, while the sum is 42.

The square root of 85639731 is about 9254.1737070362. The cubic root of 85639731 is about 440.7832656556.

The spelling of 85639731 in words is "eighty-five million, six hundred thirty-nine thousand, seven hundred thirty-one".