75552221 has 8 divisors (see below), whose sum is σ = 79440600. Its totient is φ = 71749440.

The previous prime is 75552209. The next prime is 75552229. The reversal of 75552221 is 12225557.

It can be written as a sum of positive squares in 4 ways, for example, as 105625 + 75446596 = 325^2 + 8686^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 75552221 - 2¹⁰ = 75551197 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75552229) 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 in 7 ways as a sum of consecutive naturals, for example, 19586 + ... + 23123.

It is an arithmetic number, because the mean of its divisors is an integer number (9930075).

Almost surely, 2^75552221 is an apocalyptic number.

It is an amenable number.

75552221 is a deficient number, since it is larger than the sum of its proper divisors (3888379).

75552221 is a wasteful number, since it uses less digits than its factorization.

75552221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42799.

The product of its digits is 7000, while the sum is 29.

The square root of 75552221 is about 8692.0780599348. The cubic root of 75552221 is about 422.7488276686.

Adding to 75552221 its reverse (12225557), we get a palindrome (87777778).

The spelling of 75552221 in words is "seventy-five million, five hundred fifty-two thousand, two hundred twenty-one".