121321421321 has 4 divisors (see below), whose sum is σ = 124600378692. Its totient is φ = 118042463952.

The previous prime is 121321421311. The next prime is 121321421327. The reversal of 121321421321 is 123124123121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 123124123121 = 673 ⋅182948177.

It can be written as a sum of positive squares in 2 ways, for example, as 102480015625 + 18841405696 = 320125^2 + 137264^2 .

It is a cyclic number.

It is not a de Polignac number, because 121321421321 - 2⁶ = 121321421257 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (121321421327) 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, 1639478630 + ... + 1639478703.

It is an arithmetic number, because the mean of its divisors is an integer number (31150094673).

Almost surely, 2^121321421321 is an apocalyptic number.

It is an amenable number.

121321421321 is a deficient number, since it is larger than the sum of its proper divisors (3278957371).

121321421321 is an equidigital number, since it uses as much as digits as its factorization.

121321421321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3278957370.

The product of its digits is 576, while the sum is 23.

Adding to 121321421321 its reverse (123124123121), we get a palindrome (244445544442).

The spelling of 121321421321 in words is "one hundred twenty-one billion, three hundred twenty-one million, four hundred twenty-one thousand, three hundred twenty-one".