866807540 has 12 divisors (see below), whose sum is σ = 1820295876. Its totient is φ = 346723008.

The previous prime is 866807483. The next prime is 866807549. The reversal of 866807540 is 45708668.

It can be written as a sum of positive squares in 2 ways, for example, as 574944484 + 291863056 = 23978^2 + 17084^2 .

It is a super-2 number, since 2×866807540² = 1502710622801703200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 866807491 and 866807500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866807549) 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, 21670169 + ... + 21670208.

It is an arithmetic number, because the mean of its divisors is an integer number (151691323).

Almost surely, 2^866807540 is an apocalyptic number.

It is an amenable number.

866807540 is an abundant number, since it is smaller than the sum of its proper divisors (953488336).

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

866807540 is a wasteful number, since it uses less digits than its factorization.

866807540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43340386 (or 43340384 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 44.

The square root of 866807540 is about 29441.5954051407. The cubic root of 866807540 is about 953.4711574201.

The spelling of 866807540 in words is "eight hundred sixty-six million, eight hundred seven thousand, five hundred forty".