681508594 has 8 divisors (see below), whose sum is σ = 1100898540. Its totient is φ = 314542416.

The previous prime is 681508489. The next prime is 681508637. The reversal of 681508594 is 495805186.

It can be written as a sum of positive squares in 2 ways, for example, as 668998225 + 12510369 = 25865^2 + 3537^2 .

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 13105909 + ... + 13105960.

Almost surely, 2^681508594 is an apocalyptic number.

681508594 is a deficient number, since it is larger than the sum of its proper divisors (419389946).

681508594 is a wasteful number, since it uses less digits than its factorization.

681508594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26211884.

The product of its (nonzero) digits is 345600, while the sum is 46.

The square root of 681508594 is about 26105.7195648770. The cubic root of 681508594 is about 880.0157512677.

The spelling of 681508594 in words is "six hundred eighty-one million, five hundred eight thousand, five hundred ninety-four".