681544073 has 16 divisors (see below), whose sum is σ = 813576960. Its totient is φ = 558229056.

The previous prime is 681544063. The next prime is 681544081. The reversal of 681544073 is 370445186.

It is not a de Polignac number, because 681544073 - 2⁴ = 681544057 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (681544063) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 273911 + ... + 276387.

It is an arithmetic number, because the mean of its divisors is an integer number (50848560).

Almost surely, 2^681544073 is an apocalyptic number.

It is an amenable number.

681544073 is a deficient number, since it is larger than the sum of its proper divisors (132032887).

681544073 is a wasteful number, since it uses less digits than its factorization.

681544073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4216.

The product of its (nonzero) digits is 80640, while the sum is 38.

The square root of 681544073 is about 26106.3990814513. The cubic root of 681544073 is about 880.0310220641.

It can be divided in two parts, 68154 and 4073, that added together give a palindrome (72227).

The spelling of 681544073 in words is "six hundred eighty-one million, five hundred forty-four thousand, seventy-three".