684151336721 has 4 divisors (see below), whose sum is σ = 684994927344. Its totient is φ = 683307746100.

The previous prime is 684151336657. The next prime is 684151336733. The reversal of 684151336721 is 127633151486.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 684151336721 - 2⁶ = 684151336657 is a prime.

It is a super-2 number, since 2×684151336721² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (684151330721) 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, 421794095 + ... + 421795716.

It is an arithmetic number, because the mean of its divisors is an integer number (171248731836).

Almost surely, 2^684151336721 is an apocalyptic number.

It is an amenable number.

684151336721 is a deficient number, since it is larger than the sum of its proper divisors (843590623).

684151336721 is an equidigital number, since it uses as much as digits as its factorization.

684151336721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 843590622.

The product of its digits is 725760, while the sum is 47.

The spelling of 684151336721 in words is "six hundred eighty-four billion, one hundred fifty-one million, three hundred thirty-six thousand, seven hundred twenty-one".