724901561 has 8 divisors (see below), whose sum is σ = 732131400. Its totient is φ = 717707520.

The previous prime is 724901533. The next prime is 724901581. The reversal of 724901561 is 165109427.

It can be written as a sum of positive squares in 4 ways, for example, as 2958400 + 721943161 = 1720^2 + 26869^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 724901561 - 2⁶ = 724901497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (724901581) 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 in 7 ways as a sum of consecutive naturals, for example, 32705 + ... + 50193.

It is an arithmetic number, because the mean of its divisors is an integer number (91516425).

Almost surely, 2^724901561 is an apocalyptic number.

It is an amenable number.

724901561 is a deficient number, since it is larger than the sum of its proper divisors (7229839).

724901561 is a wasteful number, since it uses less digits than its factorization.

724901561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17899.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 724901561 is about 26923.9960072795. The cubic root of 724901561 is about 898.3102289895.

The spelling of 724901561 in words is "seven hundred twenty-four million, nine hundred one thousand, five hundred sixty-one".