85878139 has 4 divisors (see below), whose sum is σ = 86088520. Its totient is φ = 85667760.

The previous prime is 85878131. The next prime is 85878151. The reversal of 85878139 is 93187858.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 85878139 - 2³ = 85878131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 85878092 and 85878101.

It is not an unprimeable number, because it can be changed into a prime (85878131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104577 + ... + 105394.

It is an arithmetic number, because the mean of its divisors is an integer number (21522130).

Almost surely, 2^85878139 is an apocalyptic number.

85878139 is a deficient number, since it is larger than the sum of its proper divisors (210381).

85878139 is a wasteful number, since it uses less digits than its factorization.

85878139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210380.

The product of its digits is 483840, while the sum is 49.

The square root of 85878139 is about 9267.0458615462. The cubic root of 85878139 is about 441.1919112355.

The spelling of 85878139 in words is "eighty-five million, eight hundred seventy-eight thousand, one hundred thirty-nine".