121420421 has 12 divisors (see below), whose sum is σ = 126304932. Its totient is φ = 116637696.

The previous prime is 121420391. The next prime is 121420501. The reversal of 121420421 is 124024121.

It can be written as a sum of positive squares in 6 ways, for example, as 1079521 + 120340900 = 1039^2 + 10970^2 .

It is not a de Polignac number, because 121420421 - 2⁶ = 121420357 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 121420421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121420021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 472325 + ... + 472581.

It is an arithmetic number, because the mean of its divisors is an integer number (10525411).

Almost surely, 2^121420421 is an apocalyptic number.

It is an amenable number.

121420421 is a deficient number, since it is larger than the sum of its proper divisors (4884511).

121420421 is an equidigital number, since it uses as much as digits as its factorization.

121420421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520 (or 407 counting only the distinct ones).

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

The square root of 121420421 is about 11019.0934745105. The cubic root of 121420421 is about 495.1809303560.

Adding to 121420421 its reverse (124024121), we get a palindrome (245444542).

The spelling of 121420421 in words is "one hundred twenty-one million, four hundred twenty thousand, four hundred twenty-one".