13521894121 has 4 divisors (see below), whose sum is σ = 13684808592. Its totient is φ = 13358979652.

The previous prime is 13521894107. The next prime is 13521894149. The reversal of 13521894121 is 12149812531.

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.

It is a cyclic number.

It is not a de Polignac number, because 13521894121 - 2¹⁷ = 13521763049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13521894101) 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, 81457111 + ... + 81457276.

It is an arithmetic number, because the mean of its divisors is an integer number (3421202148).

Almost surely, 2^13521894121 is an apocalyptic number.

It is an amenable number.

13521894121 is a deficient number, since it is larger than the sum of its proper divisors (162914471).

13521894121 is an equidigital number, since it uses as much as digits as its factorization.

13521894121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162914470.

The product of its digits is 17280, while the sum is 37.

The spelling of 13521894121 in words is "thirteen billion, five hundred twenty-one million, eight hundred ninety-four thousand, one hundred twenty-one".