840999986 has 16 divisors (see below), whose sum is σ = 1271813400. Its totient is φ = 417076608.

The previous prime is 840999959. The next prime is 840999989. The reversal of 840999986 is 689999048.

It can be written as a sum of positive squares in 4 ways, for example, as 465221761 + 375778225 = 21569^2 + 19385^2 .

It is not an unprimeable number, because it can be changed into a prime (840999989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122000 + ... + 128708.

Almost surely, 2^840999986 is an apocalyptic number.

840999986 is a deficient number, since it is larger than the sum of its proper divisors (430813414).

840999986 is a wasteful number, since it uses less digits than its factorization.

840999986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7213.

The product of its (nonzero) digits is 10077696, while the sum is 62.

The square root of 840999986 is about 28999.9997586207. Note that the first 3 decimals coincide. The cubic root of 840999986 is about 943.9130625015.

The spelling of 840999986 in words is "eight hundred forty million, nine hundred ninety-nine thousand, nine hundred eighty-six".