1686206340 has 288 divisors, whose sum is σ = 6357851136. Its totient is φ = 352235520.

The previous prime is 1686206339. The next prime is 1686206377. The reversal of 1686206340 is 436026861.

1686206340 is a `hidden beast` number, since 16 + 8 + 6 + 2 + 0 + 634 + 0 = 666.

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 = 1686206295 and 1686206304.

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 95 ways as a sum of consecutive naturals, for example, 1850485 + ... + 1851395.

It is an arithmetic number, because the mean of its divisors is an integer number (22075872).

Almost surely, 2^1686206340 is an apocalyptic number.

1686206340 is a gapful number since it is divisible by the number (10) 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 1686206340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3178925568).

1686206340 is an abundant number, since it is smaller than the sum of its proper divisors (4671644796).

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

1686206340 is a wasteful number, since it uses less digits than its factorization.

1686206340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059 (or 1054 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 1686206340 is about 41063.4428658874. The cubic root of 1686206340 is about 1190.2464804976.

The spelling of 1686206340 in words is "one billion, six hundred eighty-six million, two hundred six thousand, three hundred forty".