13261021603 has 4 divisors (see below), whose sum is σ = 13718298240. Its totient is φ = 12803744968.

The previous prime is 13261021541. The next prime is 13261021619. The reversal of 13261021603 is 30612016231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30612016231 = 19 ⋅1611158749.

It is a cyclic number.

It is not a de Polignac number, because 13261021603 - 2⁹ = 13261021091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13261061603) 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, 228638275 + ... + 228638332.

It is an arithmetic number, because the mean of its divisors is an integer number (3429574560).

Almost surely, 2^13261021603 is an apocalyptic number.

13261021603 is a deficient number, since it is larger than the sum of its proper divisors (457276637).

13261021603 is an equidigital number, since it uses as much as digits as its factorization.

13261021603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457276636.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 13261021603 its reverse (30612016231), we get a palindrome (43873037834).

The spelling of 13261021603 in words is "thirteen billion, two hundred sixty-one million, twenty-one thousand, six hundred three".