1603255681 has 4 divisors (see below), whose sum is σ = 1637367552. Its totient is φ = 1569143812.

The previous prime is 1603255651. The next prime is 1603255721. The reversal of 1603255681 is 1865523061.

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 an emirpimes, since its reverse is a distinct semiprime: 1865523061 = 149 ⋅12520289.

It is a cyclic number.

It is not a de Polignac number, because 1603255681 - 2⁵ = 1603255649 is a prime.

It is a super-2 number, since 2×1603255681² = 5140857557317547522, 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 1603255681.

It is not an unprimeable number, because it can be changed into a prime (1603255651) by changing a digit.

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, 17055865 + ... + 17055958.

It is an arithmetic number, because the mean of its divisors is an integer number (409341888).

Almost surely, 2^1603255681 is an apocalyptic number.

It is an amenable number.

1603255681 is a deficient number, since it is larger than the sum of its proper divisors (34111871).

1603255681 is an equidigital number, since it uses as much as digits as its factorization.

1603255681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34111870.

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 1603255681 is about 40040.6753314676. The cubic root of 1603255681 is about 1170.3998635691.

The spelling of 1603255681 in words is "one billion, six hundred three million, two hundred fifty-five thousand, six hundred eighty-one".