751172221 has 2 divisors, whose sum is σ = 751172222. Its totient is φ = 751172220.

The previous prime is 751172173. The next prime is 751172237. The reversal of 751172221 is 122271157.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 441588196 + 309584025 = 21014^2 + 17595^2 .

It is a cyclic number.

It is not a de Polignac number, because 751172221 - 2¹⁵ = 751139453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 751172221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (751172281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 375586110 + 375586111.

It is an arithmetic number, because the mean of its divisors is an integer number (375586111).

Almost surely, 2^751172221 is an apocalyptic number.

It is an amenable number.

751172221 is a deficient number, since it is larger than the sum of its proper divisors (1).

751172221 is an equidigital number, since it uses as much as digits as its factorization.

751172221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1960, while the sum is 28.

The square root of 751172221 is about 27407.5212487375. The cubic root of 751172221 is about 909.0333982258.

The spelling of 751172221 in words is "seven hundred fifty-one million, one hundred seventy-two thousand, two hundred twenty-one".