685919179739 has 4 divisors (see below), whose sum is σ = 686598981720. Its totient is φ = 685239377760.

The previous prime is 685919179709. The next prime is 685919179811. The reversal of 685919179739 is 937971919586.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 685919179739 - 2¹⁶ = 685919114203 is a prime.

It is a super-2 number, since 2×685919179739² (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 (685919179709) 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, 339899477 + ... + 339901494.

It is an arithmetic number, because the mean of its divisors is an integer number (171649745430).

Almost surely, 2^685919179739 is an apocalyptic number.

685919179739 is a deficient number, since it is larger than the sum of its proper divisors (679801981).

685919179739 is a wasteful number, since it uses less digits than its factorization.

685919179739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 679801980.

The product of its digits is 231472080, while the sum is 74.

The spelling of 685919179739 in words is "six hundred eighty-five billion, nine hundred nineteen million, one hundred seventy-nine thousand, seven hundred thirty-nine".