86856840 has 128 divisors (see below), whose sum is σ = 330912000. Its totient is φ = 19851264.

The previous prime is 86856839. The next prime is 86856841. The reversal of 86856840 is 4865868.

86856840 is a `hidden beast` number, since 86 + 8 + 568 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (86856839) and next prime (86856841).

It is a super-2 number, since 2×86856840² = 15088221309571200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (86856841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1816 + ... + 13304.

It is an arithmetic number, because the mean of its divisors is an integer number (2585250).

Almost surely, 2^86856840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 86856840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (165456000).

86856840 is an abundant number, since it is smaller than the sum of its proper divisors (244055160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

86856840 is a wasteful number, since it uses less digits than its factorization.

86856840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11516 (or 11506 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 86856840 is about 9319.7017119648. The cubic root of 86856840 is about 442.8615832269.

The spelling of 86856840 in words is "eighty-six million, eight hundred fifty-six thousand, eight hundred forty".