1325681681 has 4 divisors (see below), whose sum is σ = 1332550692. Its totient is φ = 1318812672.

The previous prime is 1325681657. The next prime is 1325681719. The reversal of 1325681681 is 1861865231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1861865231 = 27481 ⋅67751.

It can be written as a sum of positive squares in 2 ways, for example, as 104878081 + 1220803600 = 10241^2 + 34940^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1325681681 is a prime.

It is a super-2 number, since 2×1325681681² = 3514863838677971522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1325681081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3434216 + ... + 3434601.

It is an arithmetic number, because the mean of its divisors is an integer number (333137673).

Almost surely, 2^1325681681 is an apocalyptic number.

It is an amenable number.

1325681681 is a deficient number, since it is larger than the sum of its proper divisors (6869011).

1325681681 is an equidigital number, since it uses as much as digits as its factorization.

1325681681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6869010.

The product of its digits is 69120, while the sum is 41.

The square root of 1325681681 is about 36409.9118510331. The cubic root of 1325681681 is about 1098.5329426193.

The spelling of 1325681681 in words is "one billion, three hundred twenty-five million, six hundred eighty-one thousand, six hundred eighty-one".