74121221 has 4 divisors (see below), whose sum is σ = 74193600. Its totient is φ = 74048844.

The previous prime is 74121211. The next prime is 74121251. The reversal of 74121221 is 12212147.

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.

It is a cyclic number.

It is not a de Polignac number, because 74121221 - 2¹⁸ = 73859077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 74121193 and 74121202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74121211) 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, 34631 + ... + 36708.

It is an arithmetic number, because the mean of its divisors is an integer number (18548400).

Almost surely, 2^74121221 is an apocalyptic number.

It is an amenable number.

74121221 is a deficient number, since it is larger than the sum of its proper divisors (72379).

74121221 is a wasteful number, since it uses less digits than its factorization.

74121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72378.

The product of its digits is 224, while the sum is 20.

The square root of 74121221 is about 8609.3682114311. The cubic root of 74121221 is about 420.0627665076.

Adding to 74121221 its reverse (12212147), we get a palindrome (86333368).

The spelling of 74121221 in words is "seventy-four million, one hundred twenty-one thousand, two hundred twenty-one".