685140819 has 8 divisors (see below), whose sum is σ = 996568512. Its totient is φ = 415236840.

The previous prime is 685140793. The next prime is 685140821. The reversal of 685140819 is 918041586.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 685140819 - 2⁵ = 685140787 is a prime.

It is a super-2 number, since 2×685140819² = 938835883719981522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (685140899) 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, 10380889 + ... + 10380954.

It is an arithmetic number, because the mean of its divisors is an integer number (124571064).

Almost surely, 2^685140819 is an apocalyptic number.

685140819 is a deficient number, since it is larger than the sum of its proper divisors (311427693).

685140819 is a wasteful number, since it uses less digits than its factorization.

685140819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20761857.

The product of its (nonzero) digits is 69120, while the sum is 42.

The square root of 685140819 is about 26175.1947270694. The cubic root of 685140819 is about 881.5763837467.

The spelling of 685140819 in words is "six hundred eighty-five million, one hundred forty thousand, eight hundred nineteen".