681240389 has 8 divisors (see below), whose sum is σ = 691868448. Its totient is φ = 670626000.

The previous prime is 681240353. The next prime is 681240457. The reversal of 681240389 is 983042186.

681240389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 681240389 - 2¹² = 681236293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681240089) 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, 148559 + ... + 153075.

It is an arithmetic number, because the mean of its divisors is an integer number (86483556).

Almost surely, 2^681240389 is an apocalyptic number.

It is an amenable number.

681240389 is a deficient number, since it is larger than the sum of its proper divisors (10628059).

681240389 is a wasteful number, since it uses less digits than its factorization.

681240389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6835.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 681240389 is about 26100.5821582585. The cubic root of 681240389 is about 879.9002938860.

The spelling of 681240389 in words is "six hundred eighty-one million, two hundred forty thousand, three hundred eighty-nine".