840999999999999 has 32 divisors (see below), whose sum is σ = 1288628490612736. Its totient is φ = 477907273877760.

The previous prime is 840999999999989. The next prime is 841000000000067. The reversal of 840999999999999 is 999999999999048.

It is a Cunningham number, because it is equal to 29000000²-1.

It is not a de Polignac number, because 840999999999999 - 2⁷ = 840999999999871 is a prime.

It is a super-9 number, since 9×840999999999999⁹ (a number of 136 digits) contains 999999999 as substring.

840999999999999 is a modest number, since divided by 99999999 gives 8409999 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840999999999989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 200928579 + ... + 205071435.

It is an arithmetic number, because the mean of its divisors is an integer number (40269640331648).

Almost surely, 2^{840999999999999} is an apocalyptic number.

840999999999999 is a deficient number, since it is larger than the sum of its proper divisors (447628490612737).

840999999999999 is a wasteful number, since it uses less digits than its factorization.

840999999999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4196455.

The product of its (nonzero) digits is 9037745167392, while the sum is 120.

The spelling of 840999999999999 in words is "eight hundred forty trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".