866694819 has 4 divisors (see below), whose sum is σ = 1155593096. Its totient is φ = 577796544.

The previous prime is 866694811. The next prime is 866694847. The reversal of 866694819 is 918496668.

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

It is not a de Polignac number, because 866694819 - 2³ = 866694811 is a prime.

It is a super-2 number, since 2×866694819² = 1502319818562885522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866694811) 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, 144449134 + ... + 144449139.

It is an arithmetic number, because the mean of its divisors is an integer number (288898274).

Almost surely, 2^866694819 is an apocalyptic number.

866694819 is a deficient number, since it is larger than the sum of its proper divisors (288898277).

866694819 is a wasteful number, since it uses less digits than its factorization.

866694819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288898276.

The product of its digits is 4478976, while the sum is 57.

The square root of 866694819 is about 29439.6810274840. The cubic root of 866694819 is about 953.4298253379.

The spelling of 866694819 in words is "eight hundred sixty-six million, six hundred ninety-four thousand, eight hundred nineteen".