681440243 has 8 divisors (see below), whose sum is σ = 743579136. Its totient is φ = 619333000.

The previous prime is 681440237. The next prime is 681440261. The reversal of 681440243 is 342044186.

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

It is not a de Polignac number, because 681440243 - 2¹⁴ = 681423859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681440293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74330 + ... + 82992.

It is an arithmetic number, because the mean of its divisors is an integer number (92947392).

Almost surely, 2^681440243 is an apocalyptic number.

681440243 is a deficient number, since it is larger than the sum of its proper divisors (62138893).

681440243 is a wasteful number, since it uses less digits than its factorization.

681440243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15825.

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 681440243 is about 26104.4104128019. The cubic root of 681440243 is about 879.9863302801.

The spelling of 681440243 in words is "six hundred eighty-one million, four hundred forty thousand, two hundred forty-three".