13265651242421 has 12 divisors (see below), whose sum is σ = 13469526481068. Its totient is φ = 13064817820032.

The previous prime is 13265651242387. The next prime is 13265651242469. The reversal of 13265651242421 is 12424215656231.

It can be written as a sum of positive squares in 2 ways, for example, as 3461795148100 + 9803856094321 = 1860590^2 + 3131111^2 .

It is a de Polignac number, because none of the positive numbers 2^k-13265651242421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13265651242321) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20496845 + ... + 21134141.

It is an arithmetic number, because the mean of its divisors is an integer number (1122460540089).

Almost surely, 2^{13265651242421} is an apocalyptic number.

It is an amenable number.

13265651242421 is a deficient number, since it is larger than the sum of its proper divisors (203875238647).

13265651242421 is an frugal number, since it uses more digits than its factorization.

13265651242421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642068 (or 642001 counting only the distinct ones).

The product of its digits is 691200, while the sum is 44.

Adding to 13265651242421 its reverse (12424215656231), we get a palindrome (25689866898652).

The spelling of 13265651242421 in words is "thirteen trillion, two hundred sixty-five billion, six hundred fifty-one million, two hundred forty-two thousand, four hundred twenty-one".