121240421 has 4 divisors (see below), whose sum is σ = 121387500. Its totient is φ = 121093344.

The previous prime is 121240409. The next prime is 121240439. The reversal of 121240421 is 124042121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 96628900 + 24611521 = 9830^2 + 4961^2 .

It is a cyclic number.

It is not a de Polignac number, because 121240421 - 2²⁶ = 54131557 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121240421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121240451) 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, 72296 + ... + 73953.

It is an arithmetic number, because the mean of its divisors is an integer number (30346875).

Almost surely, 2^121240421 is an apocalyptic number.

It is an amenable number.

121240421 is a deficient number, since it is larger than the sum of its proper divisors (147079).

121240421 is an equidigital number, since it uses as much as digits as its factorization.

121240421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147078.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 121240421 is about 11010.9228041977. The cubic root of 121240421 is about 494.9361152802.

Adding to 121240421 its reverse (124042121), we get a palindrome (245282542).

The spelling of 121240421 in words is "one hundred twenty-one million, two hundred forty thousand, four hundred twenty-one".