721125511 has 2 divisors, whose sum is σ = 721125512. Its totient is φ = 721125510.

The previous prime is 721125491. The next prime is 721125541. The reversal of 721125511 is 115521127.

721125511 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is an emirp because it is prime and its reverse (115521127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 721125511 - 2⁵ = 721125479 is a prime.

It is a super-2 number, since 2×721125511² = 1040044005230022242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721125541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360562755 + 360562756.

It is an arithmetic number, because the mean of its divisors is an integer number (360562756).

Almost surely, 2^721125511 is an apocalyptic number.

721125511 is a deficient number, since it is larger than the sum of its proper divisors (1).

721125511 is an equidigital number, since it uses as much as digits as its factorization.

721125511 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 700, while the sum is 25.

The square root of 721125511 is about 26853.7801994431. The cubic root of 721125511 is about 896.7477312011.

Adding to 721125511 its reverse (115521127), we get a palindrome (836646638).

The spelling of 721125511 in words is "seven hundred twenty-one million, one hundred twenty-five thousand, five hundred eleven".