681157888 has 18 divisors (see below), whose sum is σ = 1359655514. Its totient is φ = 340578816.

The previous prime is 681157879. The next prime is 681157889. The reversal of 681157888 is 888751186.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 670188544 + 10969344 = 25888^2 + 3312^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681157889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1330131 + ... + 1330642.

Almost surely, 2^681157888 is an apocalyptic number.

It is an amenable number.

681157888 is a deficient number, since it is larger than the sum of its proper divisors (678497626).

681157888 is an equidigital number, since it uses as much as digits as its factorization.

681157888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2660789 (or 2660775 counting only the distinct ones).

The product of its digits is 860160, while the sum is 52.

The square root of 681157888 is about 26099.0016667305. The cubic root of 681157888 is about 879.8647726094.

The spelling of 681157888 in words is "six hundred eighty-one million, one hundred fifty-seven thousand, eight hundred eighty-eight".