685212840 has 192 divisors, whose sum is σ = 2476131840. Its totient is φ = 163192320.

The previous prime is 685212839. The next prime is 685212877. The reversal of 685212840 is 48212586.

It is a super-2 number, since 2×685212840² = 939033272201731200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 685212795 and 685212804.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 142719 + ... + 147441.

It is an arithmetic number, because the mean of its divisors is an integer number (12896520).

Almost surely, 2^685212840 is an apocalyptic number.

685212840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685212840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1238065920).

685212840 is an abundant number, since it is smaller than the sum of its proper divisors (1790919000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685212840 is a wasteful number, since it uses less digits than its factorization.

685212840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4784 (or 4777 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 685212840 is about 26176.5704399946. The cubic root of 685212840 is about 881.6072726708.

The spelling of 685212840 in words is "six hundred eighty-five million, two hundred twelve thousand, eight hundred forty".