866706138 has 48 divisors (see below), whose sum is σ = 2025879336. Its totient is φ = 266772480.

The previous prime is 866706107. The next prime is 866706161. The reversal of 866706138 is 831607668.

It can be written as a sum of positive squares in 4 ways, for example, as 864536409 + 2169729 = 29403^2 + 1473^2 .

It is a junction number, because it is equal to n+sod(n) for n = 866706093 and 866706102.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10503 + ... + 42938.

Almost surely, 2^866706138 is an apocalyptic number.

866706138 is an abundant number, since it is smaller than the sum of its proper divisors (1159173198).

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

866706138 is a wasteful number, since it uses less digits than its factorization.

866706138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53519 (or 53516 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 866706138 is about 29439.8732673903. The cubic root of 866706138 is about 953.4339759051.

The spelling of 866706138 in words is "eight hundred sixty-six million, seven hundred six thousand, one hundred thirty-eight".