840047404681 has 9 divisors (see below), whose sum is σ = 886605806541. Its totient is φ = 795817885644.

The previous prime is 840047404661. The next prime is 840047404709. The reversal of 840047404681 is 186404740048.

The square root of 840047404681 is 916541.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 840047404681 - 2⁹ = 840047404169 is a prime.

It is a super-2 number, since 2×840047404681² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (840047404661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 17390160 + ... + 17438398.

Almost surely, 2^840047404681 is an apocalyptic number.

840047404681 is the 916541-st square number.

840047404681 is the 458271-st centered octagonal number.

It is an amenable number.

840047404681 is a deficient number, since it is larger than the sum of its proper divisors (46558401860).

840047404681 is an frugal number, since it uses more digits than its factorization.

840047404681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96516 (or 48258 counting only the distinct ones).

The product of its (nonzero) digits is 688128, while the sum is 46.

The spelling of 840047404681 in words is "eight hundred forty billion, forty-seven million, four hundred four thousand, six hundred eighty-one".