681681057 has 8 divisors (see below), whose sum is σ = 917402976. Its totient is φ = 450206592.

The previous prime is 681681053. The next prime is 681681059. The reversal of 681681057 is 750186186.

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

It is not a de Polignac number, because 681681057 - 2² = 681681053 is a prime.

It is not an unprimeable number, because it can be changed into a prime (681681053) 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, 1061488 + ... + 1062129.

It is an arithmetic number, because the mean of its divisors is an integer number (114675372).

Almost surely, 2^681681057 is an apocalyptic number.

It is an amenable number.

681681057 is a deficient number, since it is larger than the sum of its proper divisors (235721919).

681681057 is a wasteful number, since it uses less digits than its factorization.

681681057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2123727.

The product of its (nonzero) digits is 80640, while the sum is 42.

The square root of 681681057 is about 26109.0225209601. The cubic root of 681681057 is about 880.0899774561.

The spelling of 681681057 in words is "six hundred eighty-one million, six hundred eighty-one thousand, fifty-seven".