121230421135521 has 4 divisors (see below), whose sum is σ = 161640561514032. Its totient is φ = 80820280757012.

The previous prime is 121230421135513. The next prime is 121230421135567. The reversal of 121230421135521 is 125531124032121.

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 121230421135521 - 2³ = 121230421135513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121230421135591) 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, 20205070189251 + ... + 20205070189256.

It is an arithmetic number, because the mean of its divisors is an integer number (40410140378508).

Almost surely, 2^{121230421135521} is an apocalyptic number.

It is an amenable number.

121230421135521 is a deficient number, since it is larger than the sum of its proper divisors (40410140378511).

121230421135521 is an equidigital number, since it uses as much as digits as its factorization.

121230421135521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40410140378510.

The product of its (nonzero) digits is 14400, while the sum is 33.

Adding to 121230421135521 its reverse (125531124032121), we get a palindrome (246761545167642).

The spelling of 121230421135521 in words is "one hundred twenty-one trillion, two hundred thirty billion, four hundred twenty-one million, one hundred thirty-five thousand, five hundred twenty-one".