1325551681 has 4 divisors (see below), whose sum is σ = 1325636032. Its totient is φ = 1325467332.

The previous prime is 1325551649. The next prime is 1325551687. The reversal of 1325551681 is 1861555231.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1861555231 = 9203 ⋅202277.

It is a cyclic number.

It is not a de Polignac number, because 1325551681 - 2⁵ = 1325551649 is a prime.

It is a super-2 number, since 2×1325551681² = 3514174518003851522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1325551681.

It is not an unprimeable number, because it can be changed into a prime (1325551687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10845 + ... + 52618.

It is an arithmetic number, because the mean of its divisors is an integer number (331409008).

Almost surely, 2^1325551681 is an apocalyptic number.

It is an amenable number.

1325551681 is a deficient number, since it is larger than the sum of its proper divisors (84351).

1325551681 is an equidigital number, since it uses as much as digits as its factorization.

1325551681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84350.

The product of its digits is 36000, while the sum is 37.

The square root of 1325551681 is about 36408.1265791032. The cubic root of 1325551681 is about 1098.4970330560.

The spelling of 1325551681 in words is "one billion, three hundred twenty-five million, five hundred fifty-one thousand, six hundred eighty-one".