74223521 has 2 divisors, whose sum is σ = 74223522. Its totient is φ = 74223520.

The previous prime is 74223511. The next prime is 74223529. The reversal of 74223521 is 12532247.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56415121 + 17808400 = 7511^2 + 4220^2 .

It is a cyclic number.

It is not a de Polignac number, because 74223521 - 2¹⁴ = 74207137 is a prime.

It is equal to p_4351526 and since 74223521 and 4351526 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (74223529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37111760 + 37111761.

It is an arithmetic number, because the mean of its divisors is an integer number (37111761).

Almost surely, 2^74223521 is an apocalyptic number.

It is an amenable number.

74223521 is a deficient number, since it is larger than the sum of its proper divisors (1).

74223521 is an equidigital number, since it uses as much as digits as its factorization.

74223521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 26.

The square root of 74223521 is about 8615.3073653817. The cubic root of 74223521 is about 420.2559305606.

Adding to 74223521 its reverse (12532247), we get a palindrome (86755768).

The spelling of 74223521 in words is "seventy-four million, two hundred twenty-three thousand, five hundred twenty-one".