721189253 has 2 divisors, whose sum is σ = 721189254. Its totient is φ = 721189252.

The previous prime is 721189201. The next prime is 721189267. The reversal of 721189253 is 352981127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 715723009 + 5466244 = 26753^2 + 2338^2 .

It is a cyclic number.

It is not a de Polignac number, because 721189253 - 2¹⁴ = 721172869 is a prime.

It is a super-2 number, since 2×721189253² = 1040227877285396018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721189753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360594626 + 360594627.

It is an arithmetic number, because the mean of its divisors is an integer number (360594627).

Almost surely, 2^721189253 is an apocalyptic number.

It is an amenable number.

721189253 is a deficient number, since it is larger than the sum of its proper divisors (1).

721189253 is an equidigital number, since it uses as much as digits as its factorization.

721189253 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 38.

The square root of 721189253 is about 26854.9670079857. The cubic root of 721189253 is about 896.7741523113.

The spelling of 721189253 in words is "seven hundred twenty-one million, one hundred eighty-nine thousand, two hundred fifty-three".