85878581 has 4 divisors (see below), whose sum is σ = 86392992. Its totient is φ = 85364172.

The previous prime is 85878557. The next prime is 85878623. The reversal of 85878581 is 18587858.

It is a happy number.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85878581 is a prime.

It is a super-2 number, since 2×85878581² = 14750261349147122, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85878511) 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, 256955 + ... + 257288.

It is an arithmetic number, because the mean of its divisors is an integer number (21598248).

Almost surely, 2^85878581 is an apocalyptic number.

It is an amenable number.

85878581 is a deficient number, since it is larger than the sum of its proper divisors (514411).

85878581 is a wasteful number, since it uses less digits than its factorization.

85878581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514410.

The product of its digits is 716800, while the sum is 50.

The square root of 85878581 is about 9267.0697094605. The cubic root of 85878581 is about 441.1926681471.

The spelling of 85878581 in words is "eighty-five million, eight hundred seventy-eight thousand, five hundred eighty-one".