121405305121 has 4 divisors (see below), whose sum is σ = 126683796672. Its totient is φ = 116126813572.

The previous prime is 121405305101. The next prime is 121405305137. The reversal of 121405305121 is 121503504121.

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, and also an emirpimes, since its reverse is a distinct semiprime: 121503504121 = 593 ⋅204896297.

It is a cyclic number.

It is not a de Polignac number, because 121405305121 - 2⁵ = 121405305089 is a prime.

It is a super-2 number, since 2×121405305121² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121405305101) 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, 2639245741 + ... + 2639245786.

It is an arithmetic number, because the mean of its divisors is an integer number (31670949168).

Almost surely, 2^121405305121 is an apocalyptic number.

It is an amenable number.

121405305121 is a deficient number, since it is larger than the sum of its proper divisors (5278491551).

121405305121 is an equidigital number, since it uses as much as digits as its factorization.

121405305121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5278491550.

The product of its (nonzero) digits is 1200, while the sum is 25.

Adding to 121405305121 its reverse (121503504121), we get a palindrome (242908809242).

The spelling of 121405305121 in words is "one hundred twenty-one billion, four hundred five million, three hundred five thousand, one hundred twenty-one".