13431221305 has 4 divisors (see below), whose sum is σ = 16117465572. Its totient is φ = 10744977040.

The previous prime is 13431221299. The next prime is 13431221339. The reversal of 13431221305 is 50312213431.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50312213431 = 4271 ⋅11779961.

It can be written as a sum of positive squares in 2 ways, for example, as 4855720489 + 8575500816 = 69683^2 + 92604^2 .

It is not a de Polignac number, because 13431221305 - 2¹³ = 13431213113 is a prime.

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 13431221305.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1343122126 + ... + 1343122135.

It is an arithmetic number, because the mean of its divisors is an integer number (4029366393).

Almost surely, 2^13431221305 is an apocalyptic number.

It is an amenable number.

13431221305 is a deficient number, since it is larger than the sum of its proper divisors (2686244267).

13431221305 is an equidigital number, since it uses as much as digits as its factorization.

13431221305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2686244266.

The product of its (nonzero) digits is 2160, while the sum is 25.

Adding to 13431221305 its reverse (50312213431), we get a palindrome (63743434736).

The spelling of 13431221305 in words is "thirteen billion, four hundred thirty-one million, two hundred twenty-one thousand, three hundred five".