121523242221 has 144 divisors (see below), whose sum is σ = 203518808064. Its totient is φ = 72166381056.

The previous prime is 121523242213. The next prime is 121523242229. The reversal of 121523242221 is 122242325121.

121523242221 is a `hidden beast` number, since 1 + 2 + 1 + 5 + 232 + 422 + 2 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (121523242213) and next prime (121523242229).

It is not a de Polignac number, because 121523242221 - 2³ = 121523242213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121523242229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 325799391 + ... + 325799763.

It is an arithmetic number, because the mean of its divisors is an integer number (1413325056).

Almost surely, 2^121523242221 is an apocalyptic number.

It is an amenable number.

121523242221 is a deficient number, since it is larger than the sum of its proper divisors (81995565843).

121523242221 is an equidigital number, since it uses as much as digits as its factorization.

121523242221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 564 (or 543 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

Adding to 121523242221 its reverse (122242325121), we get a palindrome (243765567342).

The spelling of 121523242221 in words is "one hundred twenty-one billion, five hundred twenty-three million, two hundred forty-two thousand, two hundred twenty-one".