681186240 has 336 divisors, whose sum is σ = 2797149600. Its totient is φ = 155602944.

The previous prime is 681186221. The next prime is 681186301. The reversal of 681186240 is 42681186.

It is a tau number, because it is divible by the number of its divisors (336).

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 = 681186195 and 681186204.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 422556 + ... + 424164.

It is an arithmetic number, because the mean of its divisors is an integer number (8324850).

Almost surely, 2^681186240 is an apocalyptic number.

681186240 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 681186240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1398574800).

681186240 is an abundant number, since it is smaller than the sum of its proper divisors (2115963360).

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

681186240 is a wasteful number, since it uses less digits than its factorization.

681186240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1649 (or 1626 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 681186240 is about 26099.5448236171. The cubic root of 681186240 is about 879.8769800484.

The spelling of 681186240 in words is "six hundred eighty-one million, one hundred eighty-six thousand, two hundred forty".