75207221 has 2 divisors, whose sum is σ = 75207222. Its totient is φ = 75207220.

The previous prime is 75207169. The next prime is 75207233. The reversal of 75207221 is 12270257.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55502500 + 19704721 = 7450^2 + 4439^2 .

It is a cyclic number.

It is not a de Polignac number, because 75207221 - 2⁶ = 75207157 is a prime.

It is a super-2 number, since 2×75207221² = 11312252181085682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75707221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37603610 + 37603611.

It is an arithmetic number, because the mean of its divisors is an integer number (37603611).

Almost surely, 2^75207221 is an apocalyptic number.

It is an amenable number.

75207221 is a deficient number, since it is larger than the sum of its proper divisors (1).

75207221 is an equidigital number, since it uses as much as digits as its factorization.

75207221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 75207221 is about 8672.2096953429. The cubic root of 75207221 is about 422.1043687408.

Adding to 75207221 its reverse (12270257), we get a palindrome (87477478).

It can be divided in two parts, 7520 and 7221, that added together give a palindrome (14741).

The spelling of 75207221 in words is "seventy-five million, two hundred seven thousand, two hundred twenty-one".