121221421 has 8 divisors (see below), whose sum is σ = 126622080. Its totient is φ = 115902192.

The previous prime is 121221403. The next prime is 121221449. The reversal of 121221421 is 124122121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121221421 - 2¹³ = 121213229 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121221395 and 121221404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17305 + ... + 23278.

It is an arithmetic number, because the mean of its divisors is an integer number (15827760).

Almost surely, 2^121221421 is an apocalyptic number.

It is an amenable number.

121221421 is a deficient number, since it is larger than the sum of its proper divisors (5400659).

121221421 is a wasteful number, since it uses less digits than its factorization.

121221421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40715.

The product of its digits is 64, while the sum is 16.

The square root of 121221421 is about 11010.0599907539. The cubic root of 121221421 is about 494.9102595538.

Adding to 121221421 its reverse (124122121), we get a palindrome (245343542).

The spelling of 121221421 in words is "one hundred twenty-one million, two hundred twenty-one thousand, four hundred twenty-one".