725959561 has 4 divisors (see below), whose sum is σ = 734116500. Its totient is φ = 717802624.

The previous prime is 725959547. The next prime is 725959579. The reversal of 725959561 is 165959527.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 191656336 + 534303225 = 13844^2 + 23115^2 .

It is a cyclic number.

It is not a de Polignac number, because 725959561 - 2⁷ = 725959433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (725954561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4078336 + ... + 4078513.

It is an arithmetic number, because the mean of its divisors is an integer number (183529125).

Almost surely, 2^725959561 is an apocalyptic number.

It is an amenable number.

725959561 is a deficient number, since it is larger than the sum of its proper divisors (8156939).

725959561 is an equidigital number, since it uses as much as digits as its factorization.

725959561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8156938.

The product of its digits is 850500, while the sum is 49.

The square root of 725959561 is about 26943.6367441368. The cubic root of 725959561 is about 898.7470470209.

The spelling of 725959561 in words is "seven hundred twenty-five million, nine hundred fifty-nine thousand, five hundred sixty-one".