86670781 has 8 divisors (see below), whose sum is σ = 87895800. Its totient is φ = 85451520.

The previous prime is 86670737. The next prime is 86670791. The reversal of 86670781 is 18707668.

It can be written as a sum of positive squares in 4 ways, for example, as 737881 + 85932900 = 859^2 + 9270^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 86670781 - 2¹⁷ = 86539709 is a prime.

It is a super-2 number, since 2×86670781² = 15023648558299922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86670791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35211 + ... + 37591.

It is an arithmetic number, because the mean of its divisors is an integer number (10986975).

Almost surely, 2^86670781 is an apocalyptic number.

It is an amenable number.

86670781 is a deficient number, since it is larger than the sum of its proper divisors (1225019).

86670781 is a wasteful number, since it uses less digits than its factorization.

86670781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2879.

The product of its (nonzero) digits is 112896, while the sum is 43.

The square root of 86670781 is about 9309.7143350374. The cubic root of 86670781 is about 442.5451341920.

The spelling of 86670781 in words is "eighty-six million, six hundred seventy thousand, seven hundred eighty-one".