13530432121 has 4 divisors (see below), whose sum is σ = 13564514212. Its totient is φ = 13496350032.

The previous prime is 13530432119. The next prime is 13530432131. The reversal of 13530432121 is 12123403531.

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: 12123403531 = 43 ⋅281939617.

It can be written as a sum of positive squares in 2 ways, for example, as 10468359225 + 3062072896 = 102315^2 + 55336^2 .

It is a cyclic number.

It is not a de Polignac number, because 13530432121 - 2¹ = 13530432119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13530432131) 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, 17040450 + ... + 17041243.

It is an arithmetic number, because the mean of its divisors is an integer number (3391128553).

Almost surely, 2^13530432121 is an apocalyptic number.

It is an amenable number.

13530432121 is a deficient number, since it is larger than the sum of its proper divisors (34082091).

13530432121 is an equidigital number, since it uses as much as digits as its factorization.

13530432121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34082090.

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

Adding to 13530432121 its reverse (12123403531), we get a palindrome (25653835652).

The spelling of 13530432121 in words is "thirteen billion, five hundred thirty million, four hundred thirty-two thousand, one hundred twenty-one".