75228221 has 4 divisors (see below), whose sum is σ = 75465852. Its totient is φ = 74990592.

The previous prime is 75228217. The next prime is 75228259. The reversal of 75228221 is 12282257.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 44702596 + 30525625 = 6686^2 + 5525^2 .

It is a cyclic number.

It is not a de Polignac number, because 75228221 - 2² = 75228217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75228211) 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, 118340 + ... + 118973.

It is an arithmetic number, because the mean of its divisors is an integer number (18866463).

Almost surely, 2^75228221 is an apocalyptic number.

It is an amenable number.

75228221 is a deficient number, since it is larger than the sum of its proper divisors (237631).

75228221 is a wasteful number, since it uses less digits than its factorization.

75228221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237630.

The product of its digits is 4480, while the sum is 29.

The square root of 75228221 is about 8673.4203749155. The cubic root of 75228221 is about 422.1436529421.

The spelling of 75228221 in words is "seventy-five million, two hundred twenty-eight thousand, two hundred twenty-one".