685513920 has 672 divisors, whose sum is σ = 2918764800. Its totient is φ = 134701056.

The previous prime is 685513903. The next prime is 685513991. The reversal of 685513920 is 29315586.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-4 number, since 4×685513920⁴ (a number of 36 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 11618851 + ... + 11618909.

It is an arithmetic number, because the mean of its divisors is an integer number (4343400).

Almost surely, 2^685513920 is an apocalyptic number.

685513920 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 685513920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1459382400).

685513920 is an abundant number, since it is smaller than the sum of its proper divisors (2233250880).

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

685513920 is a wasteful number, since it uses less digits than its factorization.

685513920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 39.

The square root of 685513920 is about 26182.3207527522. The cubic root of 685513920 is about 881.7363787600.

It can be divided in two parts, 685 and 513920, that added together give a triangular number (514605 = T₁₀₁₄).

The spelling of 685513920 in words is "six hundred eighty-five million, five hundred thirteen thousand, nine hundred twenty".