121354215421 has 4 divisors (see below), whose sum is σ = 121355707744. Its totient is φ = 121352723100.

The previous prime is 121354215397. The next prime is 121354215427. The reversal of 121354215421 is 124512453121.

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: 124512453121 = 7 ⋅17787493303.

It is a cyclic number.

It is not a de Polignac number, because 121354215421 - 2⁷ = 121354215293 is a prime.

It is a super-3 number, since 3×121354215421³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121354215427) 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, 616695 + ... + 789316.

It is an arithmetic number, because the mean of its divisors is an integer number (30338926936).

Almost surely, 2^121354215421 is an apocalyptic number.

It is an amenable number.

121354215421 is a deficient number, since it is larger than the sum of its proper divisors (1492323).

121354215421 is an equidigital number, since it uses as much as digits as its factorization.

121354215421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1492322.

The product of its digits is 9600, while the sum is 31.

Adding to 121354215421 its reverse (124512453121), we get a palindrome (245866668542).

The spelling of 121354215421 in words is "one hundred twenty-one billion, three hundred fifty-four million, two hundred fifteen thousand, four hundred twenty-one".