725211581 has 4 divisors (see below), whose sum is σ = 744811932. Its totient is φ = 705611232.

The previous prime is 725211563. The next prime is 725211583. The reversal of 725211581 is 185112527.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 185112527 = 103 ⋅1797209.

It can be written as a sum of positive squares in 2 ways, for example, as 343360900 + 381850681 = 18530^2 + 19541^2 .

It is a cyclic number.

It is not a de Polignac number, because 725211581 - 2¹⁰ = 725210557 is a prime.

It is a super-2 number, since 2×725211581² = 1051863674433039122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (725211583) 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 in 3 ways as a sum of consecutive naturals, for example, 9800120 + ... + 9800193.

It is an arithmetic number, because the mean of its divisors is an integer number (186202983).

Almost surely, 2^725211581 is an apocalyptic number.

It is an amenable number.

725211581 is a deficient number, since it is larger than the sum of its proper divisors (19600351).

725211581 is a wasteful number, since it uses less digits than its factorization.

725211581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19600350.

The product of its digits is 5600, while the sum is 32.

The square root of 725211581 is about 26929.7527095961. The cubic root of 725211581 is about 898.4382714071.

The spelling of 725211581 in words is "seven hundred twenty-five million, two hundred eleven thousand, five hundred eighty-one".